The Definitive Guide to Buying Your First Home

57% of home-buyers in LA last year were willing to buy a house sight unseen

As real estate markets in densely populated, rapidly gentrifying areas like San Francisco and Los Angeles heat up, a surprising number of Americans are willing to scoop up properties without even seeing them first.

That's according to a new survey from real estate site Redfin, which analyzed responses from more than 1,500 Americans who purchased a home in the previous 12 months. In Los Angeles, 57 percent of respondents reported purchasing a home after making an offer sight unseen. In San Diego, the share was 46 percent, and in San Francisco, it was 44 percent.

Overall, 35 percent of all home-buyers last year made an offer without going on a tour of the property.

Here are the top seven cities where successful home-buyers purchased properties that way, according to Redfin.

  • Los Angeles: 57 percent
  • San Diego: 46 percent
  • San Francisco: 44 percent
  • Chicago: 38 percent
  • Austin: 35 percent
  • Denver: 33 percent
  • Washington, D.C.: 32 percent

Young people proved far more likely than older ones to make a purchase sight unseen. While 45 percent of millennials reported making an offer on a house they hadn't visited in person, only 28 percent of Gen-Xers and 6 percent of boomers took the risk.

Redfin speculates that a prevalence of foreign investors could account for the nearly 60 percent of purchasers who bought properties blind in L.A. and other California cities.

But while homeowners might score a deal by jumping on a home before visiting, they could also be setting themselves up for disappointment. A report from Trulia found that the No. 1 mistake buyers say they made is choosing a home that turned out to feel like it was the wrong size. Almost half, or 42 percent of those polled by the real estate site, say that they picked a place to live that was either too large (9 percent) or too small (33 percent).

More than a quarter of homeowners (26 percent) also wish they had done more or less remodeling.

You can't return a home like you can return a shirt to the mall. And remodeling to suit your taste isn't easy, either. Major changes take time, money and effort. That's why it's important to visit a home before you make an offer on it to make sure it feels right in person and like a place you could actually, happily live.

Likewise, even if it seems like the next logical step in your financial plan or in your life, think twice before buying a home just because it seems like a good investment or because you're getting a good deal. Buying a home for the money isn't a smart choice, says Eric Roberge, a CFP and founder of Beyond Your Hammock.

"A single family home is not an investment," Roberge tells CNBC Make It. "It may gain money over time, but if you're looking to invest, buying a single family home and then living in that home is not the place to do it."

Becoming a homeowner is a major commitment, both of your time and finances. Don't hand over a down payment until you've taken the time to consider why you want the place. Are you planning to start a family and looking for a space you can grow into? Or are you just trying to score a good deal?

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