First of all, I'd like to say that I'm a prospective first time homebuyer, so I don't know much about loans, mortgages, etc.

Say I've been preapproved for a given amount for a house. Let's say 375,000, with 10% down (so the whole loan would be 90% of the value of the house). If I were to look at houses for 400,000, as long as I bring more cash with me keeping the 90% LTV amount, it'd be fine, right? Or would I have to bring more than that? TIA.

I would get the bank to up the pre-approval before you put a bid in on the house. Pre-approvals are generally overinflated, so the seller would be skeptical that the deal would go through if you are showing one for less than the house value. The real question, though, is if you can really afford a $400k house? We were pre-approved for $500k, but opted to buy a $250k house because we did not want all of our income tied up in a mortgage (which at $500k, it all would have and there's no way that wouldn't go into foreclosure!!).

This question belongs in the newbie thread.

What exactly is the preapproval letter wording?
From what you say about your preapproval, it seems to me the bank will loan you 90% of the home price (lower of your purchase price and bank appraisal), subject to a maximum of 375k. But it really depends on the wording of the letter. Why dont you call the loan officer to clarify.

Edit: redsox9547 has better clarified that you can go a bit over, but not ridiculously over by purchasing say 1M house.

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