Diane Nesom rents a tiny cottage — just 600 square foot and one-bedroom — at the end of a cul-de-sac in Fremont for $1,400 a month. And while that eats up about 50 percent of her take-home pay, the 35-year-old accountant regards it as “a steal” and can’t imagine moving up to a larger rental in the current runaway market.

“I earn too much income to qualify for any kind of affordable housing,” she said, “but not enough income to actually afford anything else, so I’m stuck in this middle craziness. It’s not a fun place to be.”

Maxed out on her budget — “if anything goes wrong, I’m ruined” — Nesom is among the legions of professionals who struggle to navigate the Bay Area’s escalating rental market, where it’s no longer unusual for high-end apartments to fetch $4,000 or $5,000 per month and sometimes more, especially in Silicon Valley hot-pockets like Palo Alto and Mountain View.

Though thousands of new apartments were completed around the region in the last year, the inventory can’t keep up with tech-fueled job growth. With vacancy rates at about half the national average, the demand for housing has sent rents through the roof, creating a sense of desperation for many who are being priced out. According to the most recent data, an average two-bedroom apartment now costs $2,884 in San Mateo County, $2,552 in Santa Clara County and $2,172 in Alameda County. Contra Costa County is a relative bargain at $1,835, though bets are on for how long that will last.

For most of the region, rental prices are up about 50 percent since 2010, and up about 10 percent in the last year, according to the Marcus and Millichap real estate brokerage firm, which crunched the data for this story with help from the MPF Research group.

“Rents are at a historic high,” said Caryll-Lynn Taylor, executive director of Neighbors Helping Neighbors, a Peninsula-based nonprofit that educates clients about the increasingly complex rental market and helps them navigate it. Landlords typically ask tenants to show annual income that’s triple the cost of rent. As a result, many middle-income workers are imperiled. A $2,500 two-bedroom apartment requires $7,500 in monthly income, or $90,000 per year.

“So you rule out our school teachers, most of our firefighters, many of our tech workers,” Taylor said. “And where do they go to rent and live?”

Many displaced tenants spend half a year or more searching for new apartments, she said. Of the approximately 4,900 households with incomes between $50,000 and $160,000 that the agency serves, about 370 are living in their vehicles, mostly in Mountain View and Palo Alto.

Elected officials and citizens groups from San Jose to Richmond are putting new energy behind rent control measures and related efforts to stabilize rents and prohibit unjustified evictions. Richmond has been considering strict rent control and eviction policies, while Berkeley, San Francisco, Oakland, San Jose and a handful of other local municipalities already have rent control ordinances. But many observers believe a long-term solution to the rent crisis requires a pronounced regional effort to increase housing supply, bringing it into better balance with the rate of job growth.

The pent-up demand for housing is taking a toll on Mark and Caitlin Fisch, who live with their three young children in a 2-bedroom apartment in Mountain View that rents for $2,575. A well-paid private schoolteacher, Mark has so far been able to make his payments, while Caitlin home-schools the kids. But with their lease expiring in September, they learned this month that the rent is going up — way up — to $3,600. Their options: sign a new one-year lease at the new rate, go month-to-month at $6,566, or leave. The family expects to do the latter.

“We always knew that there would probably be a raise in rent,” Caitlin Fisch said, “because that seems to be the trend. But we were thinking something on the order of 10 percent.” She suspects the hike is “spurred by the inflated salaries at the tech giants” in town, most notably Google.

Failing to negotiate “the crazy maze” of rentals has led Andrea and Frazier Hubbard to unexpected living quarters: their 26-foot trailer, in which they have camped for the last eight months on the grounds of a church in Palo Alto. Andrea is a Stanford office administrator. Frazier is a business analyst with a firm on the Peninsula. Their combined income is just shy of $100,000, Andrea said, “but you can’t really save when you’re paying thousands of dollars a month for a little apartment.”

By living rent-free in their trailer, they hope to build their savings and eventually buy a house in the somewhat more affordable East Bay.

The rental market is “super-tight,” said John Chang, of Marcus and Millichap. He drew this picture: With so many jobs being created in the last year in Silicon Valley and San Francisco, the Oakland metropolitan area has emerged as “a more affordable alternative” for renters. It’s an “overflow market,” Chang said, “where people looking for better affordability are going. The housing demands in the East Bay are not so much driven by the growth of the employment there, as by the growth in the entire region.”

He cited these numbers: In the last year, San Jose metro led the region in job growth with 59,300 new positions, a 5.9 percent jump that’s nearly triple the national increase of 2.1 percent. San Francisco registered 47,500 new jobs, Oakland metro another 20,900. There is simply not enough housing stock being added to absorb that many people, so they are either doubling up or moving to neighboring areas. And even those “overflow” cities like Oakland are starting to feel overwhelmed.

Joe McCarthy, senior project manager for San Francisco-based Bridge Housing, didn’t know what to expect when the affordable housing developer opened the application process in June for 68 units at the new AveVista Apartments on Lake Merritt in Oakland. For two weeks, lines circled the block as more than 3,700 people applied to live in the apartments, half of which will rent for between $785 and $1,399 per month. The other half, governed by Section 8 subsidies, will rent for about 30 percent of a resident’s income.

“It was the busiest lease-up we’ve ever experienced,” said McCarthy, who attributes the unusual level of interest to “the job generator that has started up in Alameda County and Oakland. We’re seeing a lot more folks looking for housing.”

Nesom, the Fremont accountant, can attest to that.

She recently went apartment hunting with her best friend, Molly Darling, who must leave her $1,300 rental in Alameda this fall. The house Darling lives in has been sold and the new landlord is likely raising the rent.

The duo checked out an open house “for a tiny — and I mean tiny — one bedroom cottage in Alameda,” Nesom recounted. “I mean, it could barely fit a twin bed. And the rent was like $1,500 a month, and there must have been at least 12 people in line when we got there.”

A $1,300 rental is just about the limit for Darling, who works as an office manager: “I can probably push it a little more than that,” she said, “but it’d eat into my groceries. My wages haven’t gone up, but the rents have exploded to the point that I can’t afford to live by myself. I’m boxed in.”

Contact Richard Scheinin at 408-920-5069, read his stories at www.mercurynews.com/richard-scheinin and follow him at www.twitter.com/RealEstateRag.