Alan
Tim Cook here. First, stop worrying "why" someone would sell using this method. Just know they do for a wide varity of reasons and these reasons are their "Hot Buttons", their motivation for selling their house. If they are comfortable and "Trust" you AND they see you are confident in what you are offering (You must believe it yourself that it works) and your offer satisfies their "hotbuttons" then you may have a deal. It's all about their motivitation and NEED to sell i.e. lost a job, divorce, job transfer and can't afford two pmts etc and do they trust you. It's not for everyone, ONLY the motivated and the sellers must be comfortable and trust you.
CAUTION: These are cool transactions, but many times a FREE house isn't really free. There is alot of responsibility and work that comes with these transactions. You must be ready to step up to the plate and do what you say you will do so be sure the risk is worth the reward. Make sure you use the correct paperwork, make sure you disclose disclose disclose everything you have agreed to in writing. They must understand the importance of ongoing communications with you and not just dissappear from the face of the earth after the closing. You may need them.
My last recommendation is, walk away from the deal if your seller is hard to work with, non-cooperative in any way. It's not worth it. It's one of those Gut-feel decisions. If they are not cooperative now, they won't be cooperative when you need them for something in the future to get the deal done. Trust me, it's not worth it.
Good luck.
