Aircraft purchase question

Hi all,

My friend from oversea want me to buy C172 for him and asking me if I
could keep his plane at my local airport for couple months before he
come to pickup. He also give me permission to fly his plane during
this time. But my question would be how would you deal with bill of
sale, tax, and insurance while the plane still in state?

Should bill of sale be under his name or my name?
If under my name, will I be liable for sales tax?
What about insurance while it park and fly in state?

Any suggestion is greatly apppreciated. Thanks all,

Paul