How much do you counter offer sellers?

[Jason Lam]

If you saw a 2br , 1bath house for 100k how much would you offer them half? or lower? (fairly good area)

I am still learning about real estate investing. and I do not have a buyers list of my own but lets say if I did have a buyer list and someone on my list will buy the house. but only for 70k. I get the price of house down to say 50k, then do you sell it to the buyer for 50k or for his 60-70k depending on negotiations.

Or do you keep this house as a rental and put a mortgage on it to purchase the property.