Lead was generated via direct mail to absentee owner, who called  me back showing some motivation to sell;b) Property is currently rented and lease term is March 2016;c) My offer will be all cash at discounted price (with option to assign the contract)....

Now I know nothing of that market it could be red hot for all I know.but smaller town markets tend to be slow movers and usually discounted purchase price from ask because there is so much to choose from.that's the basics

This means for every dollar of his lease payment, he gets a 50.88% discount and his true cost is only $0.4912 per dollar.

In ordinary circumstances I would discount a ten year mortgage completely, but with a premium of about 1% the question is basically whether you think mortgage rates are going to rise more than 2% from where they are now over the course of the next five years. 

If it's in the budget hire a cleaning service(contract with them for future services and get a discount).

Yeah, and the buyer discounts their offer by at least 1% to make up the difference.

Buy on a big enough discount to allow yourself to sell quickly and with minimal to no loss would have to be the most favorable in my opinion. 

With that much of a discount, it sounds like you have many exit strategies.

another way to create $100 more is to create a base rent and get a discount rentSay market rent is 1000you could give a discount rent of 950 base rent of 1050 to get the discount tenant must pay by 1st of the month or pay standard late fee 

That is a 33% discount!