Lots of times you can meet an agent in. the market that can at least put you in a ballpark. 

I was wondering whether I can show an executed lease between me and my LLC to make 75% of the rental income stated in the lease count toward qualifying for the new primary residence mortgage which allows me to put down only 5%.

Also, as another member pointed out, always put a maintenance spending limit per month per property in writing Anything above that should require owner approval before proceeding, unless it is an emergency type of repair such as repairing a burst pipe indoors or removing a fallen tree limb from an upstairs window. 

They will help you put everything into perspective :) 

What is you appetite and or ability to put a larger percent down?

I am nervous this will put us in a bad position for March. 

You will then have a few options with that rent money....you can put it into principal or you can start saving it to purchase yet another property.

If the price to replace is within budget I'd do it because you're putting out a newer/safer/more reliable product.2) Cost to replace the entire systems is tough to gauge without knowing the building size and style...

That could be used to put down the 15% down on the new purchase using DSCR.You could also do a "subject to" contract if you want more info I would look up "Pace Morby's" info or videos on Ytube.

Don't take it for granted and don't put all the eggs in the same basket.