The sex cost $100. Cooking motel meth was the bonus.

Steamy snaps of “Amy,” clad in a scanty white negligée and a black-and-red trimmed number, and splayed across the patchwork quilt in various positions, surely watered the mouths of Wade Weierbach and Norman Samuels.

And the online ad was all about fun. “Hey guys I'm amy I'm still in the area lol looking to have some fun last night wasn't so fun so let's hope today is I'm white girl 5'5 thick fat white ass hmu.” (As in: Hit Me Up.)

Both men apparently did just that. After texting back and forth with Amy, the men appeared to agree on a date and time to consummate.

Around dinnertime on April 29, cops in a sting waited as Samuels, 21, entered Room No. 228 at the Super 8 Motel in Allentown, Pennsylvania.

Once inside the room, cops say Amy, who was already undressed, agreed to have sex with Samuels for $100.

Money changed hands and before the deed was done, cops entered the room. But they also tacked on a narc charge after discovering Samuels was allegedly pocketing 20 bags of heroin, according to the court papers.

When pressed about the ad, Amy gave up her tech-savvy pimp named “Lil Man” who, according to police reports, “takes her photos, posts her ads, rents the motel room, arranges dates with his phone and collects a percentage of the money she earns.”

Moments later, Weierbach, 48, clearly ready to party, strolled into an all-time buzzkill. The sex police were front and center. And in his hands was what could be considered a cop’s version of a happy ending. Weierbach was lugging a brown cardboard box filled to the brim with methamphetamine ingredients, along with “numerous mason jars” that contained “cloudy liquid” giving off a “very strong chemical odor,” court papers say.

Pressed about what was in the box, Weierbach allegedly told cops he suffered from ADD and that the jars contained fuel, not meth. He later "admitted he was indeed making methamphetamine," records show. They're both being held on prostitution and drug charges in Lehigh County after failing to post bail.

The Allentown incident is just one in a string of makeshift motel meth labs cropping up countrywide. And while cops managed to swoop in before meth was batched in Allentown, often they’re too late. Then it’s only after a big bang occurs that the clandestine cookers’ lab is unveiled.

On Monday, 38-year-old Derek Anthony Gonzales was convicted in Santa Rosa Circuit Court in Florida after his meth went boom inside the Emerald Sands Luxury Inn last May. “The lab exploded and caught on fire, burning contents in the room,” according to a statement by the State’s Attorney’s office. “After the explosion, Gonzales fled the motel.”

He could face up to 70 years for the meth snafu.

Inn manager Charlene Ford downplayed the incident as isolated and overblown. “I’ve been here 11 years and this is the first time this situation happened,” she told The Daily Beast. “It was a bottle that was fizzling, not smoldering flames like the fire department was saying,” she said.

Few doubt the case back in March, when two Indiana transplants in Charleston, South Carolina thought they’d try cooking their poison in their motel room in the presence of their two children, ages 6 and 12.

The room was set alight and hundreds were forced to evacuate the motel.

Joshua Earl Lantz, 33, and Jamie Lynn Lantz, 37, who had been calling InTown Suites their home for almost a year, saw their stash in the third-floor bathroom go up in smoke.

After the blast, the mother moved her kids to another guest’s room and was seen slowly sauntering out of the room clad in only a shirt and underwear. She began whining about how she felt like her legs were on fire and lamenting, “The chemicals got me!”

The couple is being held on $500,000 bail after being slapped with charges of manufacturing methamphetamine and child endangerment and neglect. The judge lit up when the Lantzes appeared, saying "Well, you hit the big time today."

The couple blew it, according to court documents, by trying to make their meth using a technique known as “one pot,” which is a sort of like the instant oatmeal version of meth manufacturing.

In the past, producing meth required a laborious step-by-step process and a cook would set several jars in various levels of gestation to reach crystallized meth climax.

The soda bottle method is far more streamlined. A drug fiend can now nix the multiple stages of cooking, and the deviant on a time crunch can chuck the blenders, beakers, pails, and proverbial hot plate (hence the cooking). All you need, experts say, is a 2-liter soda bottle and the right chemical mix.

“You have gas inside the bottle and there’s acids and bases and solvents in there and you mix and twirl that and it reacts,” said Larry Souther, a longtime environmental scientist with the Minnesota Department of Health.

“The material inside in the liquid is floating around and it’s reacting and getting real hot,” he said.

An exothermic reaction occurs when heat rises not from a Bunsen burner but simply by swirling around inside the bottle. This requires the meth maker to untwist the cap from time to time to release pressure.

Fail to do that and, well, pop goes the weasel.

The process takes only a few hours, Souther said, and delivers “a couple day’s worth” of meth.

Explosions happen often when a hopped-up meth head neglects to unscrew the bottle. “The people out on meth aren’t thinking very well and they’re doing things that don’t make much sense,” Souther said.

That may have been the case with two Alabama outlaws who, on Thursday evening, hastily ditched their third-floor suite at the Cartersville North Inn in Cartersville, Georgia without checking out. That’s because their room and their meth combusted.

They were regulars, a witness told The Daily Beast. “I’m supposed to just say we had a water leak,” the worker said.

But the worker acknowledged the inn had in fact experienced a meth lab explosion.

The culprits were apparently husband and wife and regular guests. "They had stayed here a couple of times,” said the witness, a motel employee who spoke on the condition of anonymity, and who added that the couple paid cash and the husband flashed an Alabama driver's license. “The man was in his 50s and the woman was a lot younger. They are what we called weeklies.”

The motel worker said the address, like many motels, is a hub for many travelers heading to, or from, Florida. But it also is a mainstay for transient workers who rent out a room by the week or sometimes for the month.

The blast knocked the couple’s hotel door off its hinges and afterwards investigators found strewn on the carpeting lithium batteries and other meth paraphernalia, officials confirmed. Cartersville Battalion Fire Chief David Levey said that there was enough paraphernalia discovered that “we made the determination it was a drug lab,” he said in a phone interview.

Apparently the couple headed to a hospital where they were treated for burns and then slipped away when the fuzz arrived. It’s unclear if the couple have been nabbed since numerous messages to the Bartow County Sheriff’s Office were not returned.

The DEA’s El Paso Intelligence Center (EPIC) counted 1,321 meth lab incidents in the U.S. recorded from 2008 through 2013. That’s just the ones that are discovered.

How did the meth lab leap from trailer parks in the sticks to populated motels or the trunks of cars or even Wal Mart?

The “one pot” method is one of the main reasons meth has become so mobile. “Meth labs these days don’t require much of the beakers and cannisters like they used to. All it takes is a soda bottle to make meth,” DEA Special Agent Matthew Barden told The Daily Beast.

After all, the motel rooms are more than just a place to crash for a night or two. They’ve become semi-permanent homes. And the establishments where meth labs are exploding or cooking on the sly are not necessarily five-star joints.

“Motel rooms are nasty as it is even when they clean them,” Barden quipped, before stressing that the lethal nature of the practice is nothing to snicker at. “It’s one thing to do this behind your own closed doors but when you do it in a motel you are putting so many people in danger.”

And while the soda-bottle crystal meth product is pretty pure and potent, most of the best product, Barden said, is still being shuttled across the border from Mexico. “The Mexican product is 95 percent pure and it’s made cheaply in massive quantities,” he said.

The artisanal batches of meth in motel rooms make up “a small portion of complaints” Barden said and the DEA must keep on going for bigger game. “The meth [in motels] is a threat but in the eyes of the U.S. Government the biggest threat is still to investigate and target the largest drug traffickers.”

You have to wonder how many clueless motel guests are resting their heads inside rooms next to meth labs right now, or renting rooms that were drug joints just days ago, perhaps still caked with chemicals.

The exposure to the jugs of ether and anhydrous ammonia can do real damage to unwitting neighbors. “If you’re breathing the chemicals being cooked or being vented it can travel in the air and into your mucus membrane and it burns,” Souther said. Cleaning companies have begun specializing in meth eradication but there are strict guidelines that the U.S. Environmental Protection Agency has set out.

When asked about the motel meth lab phenomena, an EPA spokeswoman confirmed to The Daily Beast their agency “is aware that meth labs may be found in all possible locations, including hotels, motels and other multiple unit dwellings.”

And motel meth cleanup is no joke.

“When I enter a motel room with meth and get a whiff of the stuff, I know to quickly shut the door and run to get a hazmat team in there,” one cop who has encountered several meth labs in motels over the years told The Daily Beast.

It’s dangerous and can break the bank. A meth motel room can run as much as $10,000 to sterilize. And that includes a very intricate cleanup effort.

“The meth, whether it’s cooked or bottled, it gets everywhere, the same as someone who smokes in a house,” Souther said.

There’s spillage from the chemicals and the fumes that stick to the walls. Not to mention the potential chemical reactions to strong cleaning products.

Carpet, curtains, bed and furniture must be removed, Souther said, along with a proper scrubbing. “You go in and wash everything once with water and detergent and then rinse and wash it and rinse and wash it three times with just water,” he said.

The potent drug is something that few can resist once they’re hooked.

At an Angola, Indiana Red Roof Inn, a trio was caught cooking meth last week, according to police. Christopher Moon, 32, and his 21-year-old pal Desiree Hull allegedly reached out to Tyranny Frye (also 21 years old) to help them cook up a batch last week before local sheriff's deputies moved in.

Frye had been in and out of jail after trying to kick the meth habit. His mother had no idea that he somehow had managed to possibly learn how to make it.

“He progressed from buying the stuff to making it, which I’m not positively sure what’s going on,” Carole Frye said, relating the recent felonies Frye and the other two had racked up; which include producing meth and possessing drug paraphernalia.

Carole said she knew for certain that her son had gone from smoking to injecting himself with the drug. “Ty progressed to shooting it up,” the mother said through tears. “ I was heartbroken.”

Carole said her recent visit to see her son in jail revealed a broken boy who is losing hope.

“I talked to him and he was saying ‘I wish they would just shoot me,’” Frye said. “He doesn’t think there is any point in going on.”

Already Frye has lost his longtime girlfriend, whom his mom described as “the love of his life,” and was pleading with her how sorry he was for getting into trouble again.

Tragically, were it not for Indiana’s bureaucratic system being unable to help the mother and her son, the addiction may have been kicked long ago.

“I went before a judge and handed two typed pages proving that I had gone with Ty, [he] willingly with me, to find help and nobody would help us,” she said.

Carole says Frye from the first was bullied into becoming a meth addict.

“He was 15 years old the first time he got involved with meth,” Carole told The Daily Beast days after she visited her son behind bars. “He was at a house where he wasn’t supposed to be and he went into the other room to see what they were doing and that’s when he saw them smoking meth.”

The so-called friends then decided to force Frye to partake. “Because he had seen them they held a knife to his throat and made him smoke it too,” his mother said.

Frye’s dream in life was become a lawyer, not a law breaker. She believes he was trying to get on the straight and narrow path—but he strayed and was without many options.

“I think they run out of places to be,” she said of meth addicts who opt for motels. “They burn so many bridges that at a certain place they don’t have anywhere to go.”