Although the advice regarding proof of funds is correct, that provides almost no assurance. I know more than a dozen hard money lenders who'll give me a proof of funds letter. It basically states that if the transaction meets certain criteria, the money is available. (Criteria tend to be a purchase price no greater than 65% of after repair value minus repair costs.) So don't get reliant on "proof of funds." Heck, if you're willing to sell the property for 65% of ARV minus repair costs and you've got some time, just put it on the MLS. The advantage of investors buying at a discount--to the seller--is a very quick close and the ability to sell the house in "as is" condition. There's only one national network--a franchise--that I'm aware of that does that. They're the ones who advertise "We Buy Ugly Houses." Otherwise, investors tend to be local or, at best, regional. One way to help tell if they're legit is to ask them about past transactions and ask them for references which you can check. Another tip: Try to determine if the company making the offer actually plans on buying or whether they plan on assigning the contract; the latter are called "wholesalers." There's nothing wrong with wholesalers at all, but for the transaction to work, the wholesaler then has to find someone else to assign your contract to. You often can identify wholesalers by looking for language in the purchase offer stating that the purchaser is "XYZ and/or assigns." Again, there's nothing wrong with wholesalers; I know plenty of legitimate ones. It's just that there's an additional way for the deal to fall through. Hope that helps.