Once its done, its done and the seller has no ability to get the property back except to buy it back from the new owner.

Now, how would I come up with my offer price for the seller?

The seller says the house needs approximately 50K worth of work.

Also, does the seller pay the whole 6% realtor commission?

I am new to getting financing on properties as my other 2 properties I was lucky where the seller let me do payments to them directly on short 5 year loans at very reasonable interest rates.  

The asking price is 115k and I could pay cash for about 90-95k (getting the rest from seller or family).

Considering the seller is motivated , positive cash flow property and the owner is just trying to get it off his portfolio. ....How can you structure that deal

In terms of prospecting, if you're referring to sellers, not sure if brokers are allowed to do direct mail.

I am a motivated 25 year old living in the DFW area.

I am super motivated and eager to see what will happen.