Gambler X is a professional sports bettor who makes his living betting legally in Las Vegas. He has agreed to share insights and experiences in the betting industry but prefers anonymity to keep his edge against the sportsbooks.

I am a professional gambler in my mid-30s, based in Las Vegas. Although I dabble in a variety of gambling ventures, sports betting is my bread and butter. For the past five years, it has been my family's main source of income, fed and clothed my children and allowed my wife to go back to school to finish her education. It has given me the type of personal and professional freedom that I try not to take for granted.

The life of a professional sports bettor is filled with worry. Imagine busting your butt all day, only to have the difference between a winning and losing day decided by a two-point conversion in a preseason game (that happened to me a couple of times this year). Sometimes those bad days turn into bad weeks, which turn into bad months ... which turn into bad years. It's impossible to not go at least a little crazy from time to time. It's basically a job requirement.

The worst part of it is that the day-to-day variance isn't my main concern anymore. What really keeps me up at night is the fear of losing my edge. I've been asked many times what my biggest fears are for the future of sports betting, and my answer is always the same: change.

Nevada was a bubble, and it was nearly impossible for a U.S. citizen to make a living betting sports (at least legally) unless he or she lived here. But with legalized sports betting now in five states (and counting), that change is here.

And I'm not happy about it.

I was 18 years old when I made my first sports bet. It was with a bookie (gasp) in the small midwestern town where I grew up. I was spending most of my days grinding away in an underground poker game, in which the only thing more common than a bookie was a broke degenerate trying to place a bet with him.

It didn't take me long to figure out that all the bookies were doing was adding a few points to all the local teams, just locking in value. But if you tried to take the other side, they would cut you off after a few bets. What's a young man trying to find an edge supposed to do?

My answer was to start taking bets myself.

I undercut the market by offering the same numbers as everyone else but not charging juice. By offering all my bets at even money, I quickly became the favorite bookie of every casual bettor in town.

It was a worthwhile venture, but it didn't make me rich by any means -- and I still didn't really understand much of anything about sports betting. I did understand that being a local bookie was a terrible way to try to make a living and that moving to Vegas to try to make a living being a professional gambler was probably not my best idea. But it had to be more fun than spending the rest of my life in a dreary midwestern town. And I knew I wouldn't be able to live with myself if I didn't at least try to make it in Sin City.

My big break was that the one guy I knew who lived in Vegas had a similar idea and was already way more successful than I could ever dream of being. I was lucky that he was willing to show me the ropes and that I picked it up quickly. My earliest memory of being a pro sports bettor in Vegas is driving 40 minutes north of The Strip to pick off bad numbers at the then-independent Aliante sportsbook -- nearly every single afternoon.

Being a professional sports bettor is a lot more than just picking winners. It's about getting action down with casinos that actively go out of their way to deny your bets or ban you from the sportsbook entirely. It's about getting five figures on a game and not moving the line. It's about finding an edge and pushing that edge hard enough that you make a great living but not hard enough that the sportsbooks figure out where they are screwing up.

All of that might sound easy -- and to a certain extent it is in Vegas, where there are so many casinos and gamblers that it's easy to stay anonymous -- but it takes time and plenty of patience. And it has gotten harder in Vegas.

The number of sportsbooks here that offer mobile apps has basically tripled. And while my bet sizes have quadrupled, my edge has decreased. It's well documented that most books are banning winners, but my edge has decreased for other reasons. As much as everyone wants to make fun of them, sportsbooks are getting sharper. They are making fewer and fewer egregious errors and doing a better job of staying in line with the sharper overseas markets.

I used to be able to see a bet that was out of line with the market, hop in the car and go grab it with ease. Those days are long gone -- and will never come back.

Now that legal sports betting has spread to other states, there are more variables and more information to learn.

Legalization means more places for sharp bettors to sneak bets through without moving the market. More casinos sharing liquidity and information to stay one step ahead of bettors. More jurisdictions and hodgepodge shops where one is the majority owner, but lines are set by another, and software is provided by a third. It's just more stuff to make my life miserable.

And it means I've been traveling all over this summer on fact-finding missions.

I've visited Delaware, New Jersey and Mississippi to see how things are run. I traveled all over to test out the new markets. I pushed them hard. A lot of bets at max limits, just testing every place over and over again with the idea of trying to find some place outside of Nevada that would be sustainable for a professional bettor longer-term. I haven't been particularly impressed.

Take Dover Downs in Delaware, for example. The book is owned by the state lottery, and William Hill sets the lines and decides what bets to take for a very small percentage of profits. This strategy leads to dealing one-way lines, on which they are taking action on only one side and then banning anyone William Hill in Las Vegas deems likely to win money. If the State of Delaware is the primary beneficiary from the sports book, then shouldn't it be required to offer a fair system in which anyone can play?

In Mississippi, I mostly targeted MGM properties. The staff were friendly, and they took big bets with no issues. But as I suspected, they mostly mirror MGM Las Vegas' lines, so there is no real opportunity for me.

And New Jersey? It was supposed to be the golden goose, but there have been several hiccups. Don't even get me started on the recent FanDuel fiasco.

For me, independent books that set their own lines and manage their own risk are the lifeblood of my business. They mean more chances to pick off bad lines, opportunities to arbitrage and more places I can go fire the same bet at the number I want. Of all my travels to the new states, the most disheartening thing to me was how few of those opportunities were out there.

The manager at every sportsbook I visited is underqualified and doesn't make a move without checking with the bosses in Vegas first. They aren't really aware that for someone who does this for a living, one tiny mistake or moment of complacency can cost big time.

There are a few lucrative spots in these other states, but the cost to exploit them is so prohibitive that I'm better off crawling back to the desert and trying to gather the facts about the new and ever-changing environment.

That's just the glamorous life of a sports bettor.