I've heard that banks have a set discount rate from the BPO (Broker Price Opinion) that they will not go below.  

Another note is that both Home Depot and Lowe's give a Military discount of 10%.

The more liquidity (cash, stocks, bonds), not 401K as that is discounted, you have the better as that mitigates risk, and since you'll almost certainly be obtaining a recourse loan your guarantee needs to mean something and that is based on the amount of liquid funds you bring to the table.Find a property that is "safe".

I need her cooperation to show the property and even offered her a discount in the last month's rent until she said the ac broke again and she was not going to pay for it. 

I submitted an offer on a foreclosure at 1K above asking price. The property looked like it required virtually no work.After my offer was accepted I found out it required substantial work. It has an illegal addition w...

 $15,000 discount to take an underground tank that you estimate has a 50/50 chance of leaking?  

You can then buy houses at a discount for cash, do some remodeling. get it appraised at the higher value then do a cash out refi with a conventional loan to get your cash back.

So if that professional Agent can't find a (retail) Buyer/Occupier to pay say $90k, how will you find a (discount-seeking) Investor to pay the same? 

Those kind of discounts last less then a few hours and are purchased with cash.

My PM in Raleigh will send me average rents for the previous year 90 days before lease end and their preferred range and ask what I prefer for 1-year and 2-year leases (I prefer 2-year at a slight discount).