I am wondering what method can I use to pull this equity out of the home to purchase more homes through owner financing techniques. 

Lies to Watch Out ForThe brokerages have developed scripted techniques and tactics to build trust with owners.

To be successful at the technique you have to be pretty shrewed and willing to push the Caveat Emptor factor on your buyers, or you have to be very, very, very good at finding REAL legit good deals (this is not super common). 

Don't let your scepticism interfere with your opportunity to learn new methods, techniques, and strategies.

although they both are interdependent.The best way to understand costs is to get a Floor plan drawn and get quotes from at least 3 people in the area who have done ADU'sIt's always a good idea to involves a professional right from the start, especially someone who is experienced as they will suggest techniques that could bring value and save money in the long run.

I justified selling my house to buy two as using the stacking technique.

The technique is called a 1031 exchange or a like-kind exchange.

So what’s the technique used for discovering there’s a secret extra tenant living there?

Is there any other techniques that is more better vs another to examine repair/rehab cost while analyzing property.Hope to get lot of stories n ideas from you guys.

we do a lot of infill building.. this only works in HIGHLY desirable areas @Wayne Brooks  as Wayne states not sure were your thinking the value play is here.now there are plenty of folks that buy cheapo lots in FLA like Lehigh acres then sell for a few grand more on contracts those are the land flipping guru's you see that's what they teach.. and there are millions upon millions of lots available for this type of activity generally in FLA  and West Texas  AZ CA and other areas that had massive land speculation booms in the turn of the century.. think Lancaster Palmdale in CA there are million plus platted lots there that get traded around at tax sales every year.to find land with value to builders you need infill in established areas.. close to down towns.. in areas that are regentrifying .. lots that have shadow plats beneath them. or you can split using a lot confirmation technique ( common in Portland)  you need to work areas of Scarcity ..