SAN FRANCISCO >> Check out rental sites for San Francisco, especially the trendier parts: Well over $3,000 a month for a one-bedroom flat and nearly $5,000 for two bedrooms.

Finding a place to live has become so expensive and emotional that city supervisors are considering a 45-day moratorium on luxury housing in the Mission District, one of the most diverse neighborhoods in the city.

The district, home to taquerias and corner markets, is now teeming with Silicon Valley workers and the pricey restaurants that cater to them.

Fancy high-rises are planned to take over dilapidated street corners, including one that tenant activists have dubbed the “Monster in the Mission,” a 345-unit building with rents projected to start at $3,500.

The growth is pushing out longtime tenants, say hundreds of people who crowded San Francisco City Hall last month to support the moratorium and urge a time-out on evictions.

They say that working families, especially Latinos, are being forced out to make way for market-rate housing and the city has a responsibility to fight back.

The moratorium would give the city room to purchase some of the land available in the Mission, to develop hundreds of affordable housing units for lower-income and middle-income families.

“We were traditionally the most working-class neighborhood, dating back to the Irish and the Italians in the Gold Rush, and it’s no longer,” says Gabriel Medina, president of the San Francisco Latino Democratic Club. “It’s trending into something that’s not a working-class neighborhood.”

The district has lost lower-income and middle-income households, according to a recent study by the nonprofit Council of Community Housing Organizations. Families with households making $50,000 to $75,000 made up a quarter of Mission households in 2000; now they make up 13 percent while households with incomes of at least $100,000 have increased.

Tuesday’s vote is largely symbolic —it faces steep odds of passage— but telling of how lawmakers are desperate to do something about housing in a city where prices are among the highest, with no signs of abating.

Opponents say the way to make more housing affordable is to build more and that artificial bans won’t bring prices down.

The moratorium needs nine of 11 votes to pass. The board took the unusual step of skipping a committee vote and fast-tracking the issue straight to the full committee.

According to the city, more than two dozen projects would be affected, including the “Monster.”