OPT will come in the way for certain banks...As far as I know..Wells Fargo needs atleast H1 visa...

also..it doesn't make sense to transfer the loan to your name, but the house be in your friend's name...the bank that will be taking the loan in your name isn't that stupid either...you taking the loan means the house too will be tied to that loan...and if you default the loan..your bank gets the house..

so if your friend is looking to transfer the loan to you..he will have to give his house to you too..