Millennials aren’t exactly jumping for joy after purchasing their homes. About four in 10 millennials are already homeowners, according to a new survey of over 600 millennials (age 21-34) by Bank of the West. Yet it turns out that 68 percent of them are feeling buyer’s remorse — almost double the amount of Baby Boomers who say they have regrets. “Millennials are so eager to become homeowners that some may be inadvertently cutting off their nose to spite their face,” says Ryan Bailey, head of Bank of the West’s retail banking. Here are the biggest areas of remorse.

Overspending on the down payment

Roughly four in 10 millennials felt they made poor financial choices when it came to purchasing their home. Part of the problem seems to revolve around the down payment. The survey found one in three millennials dipped into their retirement accounts to pay for their homes — a trend Bailey calls “alarming.” “Borrowing from your retirement may make sense in special circumstances, but it’s definitely not a recommendation,” Bailey tells CNBC Make It. To keep from getting squeezed, think about what you can afford as a monthly payment, and don't forget to include taxes and insurance in your calculations, Danielle Hale, chief economist for Realtor.com, tells CNBC Make It. Use filters on home search sites and price alerts to make sure you're not shopping for a home above your budget. "Don't fall in love with something that's already out of your price range," Hale says.

Underestimating ongoing costs

When you buy a home, the expenses don't stop once you move in. Millennials understand basic costs, such heating and electric bills, but Bailey recommends also considering how much time and money it could take to mow the lawn, clean the house or deal with leaky faucet. “When you’re a homeowner, you can’t call your landlord to fix things, so you want to make sure you have a little extra cash in the bank,” Hale says. It's a big transition going from renter to homeowner, so make sure to take some time to learn about the maintenance costs associated with potential homes.

Settling for something that's not quite right