I don’t see a huge disparity in the way short sales are financed but if you are coming in with cash most lenders authorizing the short sale will want to see proof of funds. So if you have the cash in your account it doesn’t matter how it got there. Lottery, heloc whatever. After the purchase if you want to refi to pull the money back you can but the rate “may” be a bit higher then a purchase loan. Hls can abswer that. How much you can pull out will depend on the lender