I hope you do better. 

There seems to be a bit of hostility here from the contractors, and this was really just a question so I could better understand and more easily work with contractors.This question was for a first-time encounter with a new contractor not recommended to me by anyone I know.I am happy to give weekly checks for progress, purchase all materials upfront including all the fittings, nails, caulk, and whatever else the contractor chooses.

Then, the lease will be up in the summer when the demand is higher to get better returns 

The fact they ask you to do this is not only a red flag for obvious reasons, but also because, they should know better how risky this is for you and if they had true good intentions they would have understood that and not offer you that option.What you can do is tell them..

Earning 25% is better than paying down a 5% mortgage. 

You would do better to hold the stats until someone asks about the area and then drop the knowledge for them in direct response.

Walking away is better than proceeding and finding yourself upside down and owing money . . . there are always more deals. 

I think the place needs a little TLC and it would show better.

Maybe we just need to find a better laundry service. :) 

What or who do you suggest I speak to or learn from to better understand my options for mortgages?