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that write your own mortgage thing; how to learn about it
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you are asking about a common, simple practice of holding the mortgage when selling a house you own outright. typically called seller financing.  say i am 70 and wish to downsize. the money i sell my house for will likely be in the bank at today's awful rates. now, a buyer likes my house, and has 20% down, but due to some medical bills for his deceased wife, he and his new wife are struggling to get financing. i offer to let them pay me as if i were the bank. we agree on the rate, i have a lien on the house just as a bank would, and my mortgage with them requires the usual fire, theft, vandalism insurance. when i die, my heirs will get the income, or the buyer can pay in full after i'm gone.  in response to comment "how do you do that? what's the paperwork?" fellow member @littleadv has often posted "you need to hire a professional." not because the top members here can't offer great, accurate advice. but because a small mistake on the part of the diy attempt can be far more costly than the relative cost of a pro. in real estate (where i am an agent) you can skip the agent to hook up buyer/seller, but always use the pro for legal work, in this case a real estate attorney. i'd personally avoid the general family lawyer, going with the specialist here.
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