If the buyer can't get a regular mortgage you can sell it on a
contract for deed. The buyer makes payments to you at some
interest rate and when it is paid off, buyer gets the deed. You
have made some extra income over the sales price.
If buyer fails to make the payments, you get the place back.
Now in this case you may need legal help.
Not true in all states. Here in Colorado a "contract for deed" or "installment sale contract" must be enforced in the same manner as a "deed of trust" usually associated with a mortgage, with foreclosure actions administered by the public trustee, etc.
Regardless of where you reside, consult a competent attorney practicing in real estate law, and anyone who purchases real estate without a commitment for title insurance is an idiot who deserves what might happen down the line.
Realistically, if you own a $200K property and the real estate brokers charge a 6% commission ($12,000 usually split between the listing broker and selling broker) you will walk away with about $188K less usual closing costs (about 1% or $2K).
Title insurance costs might be $1K or so (negotiable between buyer and seller), and a lawyer might charge $350 per hour for the time necessary to prepare the documents and close the transaction (actually, the title insurance company will handle just about every except the contract documents, with a minimal "closing fee" added). Unless there are some really ugly issues clouding the title to the property you should be able to close a $200K house deal for no more than $6K to $7K total, legal fees and title insurance costs, assuming a truly willing buyer and seller.
Of course, you can always do the "do it yourself" routine, and maybe you will walk away without lawsuits nipping at your heels for a few years, or maybe not. After all, the definition of a "contract" is nothing more than the agreement between the parties, but when it is written in Crayon on a Big Chief tablet you may have some difficulties at the courthouse as lawyers parse the language.
Do it right the first time so you can walk away without having to look back.