I personally manage the people side (collections, move-out, promote, screening, selection & move-in) and off load the physical efforts. 

The existing framing isn't built to support the weight of a second story so it's not as simple as adding a couple of 4x12 beams to raise the first floor ceiling.

Take the time before you invest to down load and study the Ontario landlord /tenant regulations.

This is beginning to raise some flags in my mind and I wanted to get some advise from this group as to how much documentation I should obtain  related to the business and how much weight I should give to the business, assets and income. 

welcome to BP, i recently moved from MD to FL but i went to a few REIA meetings up there, loads of helpful and friendly investors in the area

No set standard, my investor clients vary in what they are looking for... most look for basic value purchase.. ie. cost of investment vs return  (roi)As to Cash Purchase, as a seller would not put weight on a "cash offer", regardless how they buy, as a seller your going to get a check from escrow, and I see a lot of offers from "cash" buyers, imho they can be more risky since a person with all cash can change their mind at any time during escrow if they see a better deal.Price is the #1 factor on any property, no mater what the condition the only factor in a property not selling the very fist day is price.

I've had a few tenants who don't do full loads of laundry when I'm paying for water.  

I was wondering more, thinking out load, how much does knowing these key people really help me in the long run?  

There are usually some at those trying to off load some properties.

I had considered stucco, but am afraid of the weight factor.