Need help with an investor and a cash purchase

[Ryan Pearlman]

 If someone lends me $300,000 to purchase a property in cash, is it as simple as them just sending me the cash and me sending it back when the loan from the bank comes in ?

In this specific deal, someone was going to send me 280,000 to purchase a property in cash. I am pre approved for a loan from the bank and when the bank has the funds ready for me, I was going to take that money and pay back the investor plus an extra $3000 for the 30 day loan. Is there any paperwork, taxes or extra steps I need to take or is it as simple as the investor just sending me the money?

Keep in mind the bank will be aware of all details of this deal.