A Proof of Funds letter is evidence of immediately available funding for a purchase. If you have sufficient funds, your bank should provide a brief Proof of Funds letter for you, but sometimes, due to red tape, even if you have the funds, they still may not. Ask me how I know!
A hard money lender might give you a Proof of Funds letter.
Depending on whether the short sale borrower's lender has any specific wording requirements for the Proof of Funds letter, you might be able to simply ask a friend for a Proof of Funds letter. Your friend will likely want to make the loan "subject to property inspection."
If the short sale borrower's lender has a problem with the language in your Proof of Funds letter, they'll let you know. If the short sale is destined for success, because it's a "win win win win" for the seller (borrower), the seller's lender, you, and the ultimate buyer, they're probably not going to give you too big of a problem with the language of the Proof of Funds letter.
Dick, if you'd like to discuss this in more detail. Please feel free to give me a call.