If the market is anywhere near as hot as some in this thread are saying it is then don't buy. Just wait until it cools and the inventory rises. Unlike DJR210, I recommend never overpaying for a home. This type of emotional buying is bad for a number of reasons... mainly you'll hate yourself when in just a few short years you'll have neighbors moving in for 100k less than what you paid for the same house. I do agree with DJR210 on getting your own financing. If your realtor insists that he can get you a better deal then tell him to off and threaten to find another realtor.
If you truly want to be a responsible buyer then spend no more than 30% of one income on a home, and I'm being generous here. If that's not possible then look for a cheaper house, or condo, or wait until you make more money, or the market turns into a buyers market. Lenders, Realtors, and IDIOTS will tell you to spend more, but they don't consider college tuition for your kids. They don't consider your retirement, yearly vacations, escorts, and others things that are important. It is far more better to have money saved and invested than to own a home. You can easily do all three if you're smart and patient, but whatever you do don't get caught up into a buyers frenzy that will eventually cost you your home and family.
Do your homework on bank-managed bi-weekly payments vs self-managed bi-weekly payments... both can knock 5-7 years off of your mortgage and 10's of thousands or more off the interest paid. Now... you have some homework. One more bit of advice... try to accomplish this on your own before marriage and do everything possible to protect it before you get married. You work hard for your money and you should work harder trying to keep it.