Approaching pre-forclosed and foreclosed homeowners?

[David Polius]

Hello community! I've been reading up on how to find good deals, im interested how buying from someone who has not listed their property for sale works. Some forclosed homes on zillow are on there for thousands of days (which would translate into years of homeowmers not paying mortgage?) how would you approach an owner of that sort? Is that who you send the "yellow letters" to? If thats the case what would it say? If for example his or her property was bought for 300k, 10 years ago, and now its been forclosed for two years, that would mean they paid mortgage for 8 years and have lets say 200k left to pay. So what would be the offer? Am I even asking the right questions here? Would love to learn more about this, and if anyone can explain more in depth, with more examples I'd appreciate the time. Cheers!