re: Can I get some advice on cosigning a mortgage refinance?

I would have him contact his lender and see if an in house refi is possible, some lenders do this to retain notes if they are in good standing, often much cheaper and simpler this way.

I would not take out a loan in my name against property titled in someone else's name, way too many unforeseen things can go wrong on both ends and situations change.

just my 2 cents