This summer is on track to be the best home buying season since 2006, with robust demand and a corresponding growth in supply, according to Realtor.com. But before you get excited, realize there are obstacles that might keep you on the outside looking in.

Be prepared: "Most people search for a home and think about the mortgage after they've found a potential purchase. This is akin to starting retirement planning after you're retired," says Warren Goldberg, president of Mortgage Wealth Advisors in Plainview.

advertisement | advertise on newsday

If you have a history of late payments, you expect trouble getting a loan. But your "utilization rate" can also lower your credit score.

"Don't close credit cards with large lines of available credit and only keep the ones with a balance. This increases your utilization rate of available credit, causing your scores to drop," explains Tom Mingone of Capital Management Group of New York in Manhattan.

You're also not in good stead if you don't have enough income to support your debt load, says Matt Hackett of Equity Now, a Manhattan mortgage lender.

Preapproval isn't the end game: "Lenders pull credit [reports] throughout the process. Making other large purchases or opening new lines of credit can jeopardize your loan," says John Walsh of Total Mortgage Services in Milford, Connecticut.

Sometimes it's not you: The house could be problematic. For example, "the appraisal on the property doesn't support the purchase price," says Sam Heskel of Nadlan Valuation in Brooklyn.