Even if you can clear 75% of your rent, the banks are still likely to discount that percentage for borrowing calculation purposes anyway.

Rather, I plan to focus on rewarding long term tenants who pay on time with rent discounts for new leases (higher discounts for longer leases ala Mike Butler) and upgrades (really, things I mostly plan to improve anyway).

If the electric is showing age and stress and the profit is there and i discounted the house when i purchased it. knowing that i need to update the electric.

They are risky transactions and buyers expect a discount to market value to make up for the risk.

There are some northern cities that could be interesting for buy-to-let: Zaragoza, Burgos, Logrono, Lleida,... all these cities have small-medium size universities and good public services and you could buy for a discount. 

Was it greater than 10% discount to list price? 

It seems that if you get the note at a discount (i.e., less than property value), worst case scenario you get the said property, and the equity (assuming there is some) in the property.  

NAR also has a partnership with Placester to give NAR members a hefty discount on there services (last time I checked it was 50% off), I'll go more in-depth more later. 

In my experience thus far, there aren't going to be a ton of great options where you are going to get a significant ROI while still keeping liquidity.One thing I am doing is investing heavily in my Employee stock purchase program (ESPP) as i can buy shares at a 10% discount 4 times per year then turn around and immediately sell to keep the profit.

Most houses like this have to sale at a discount because they are not zoned for what the are setup as.