Once you renovate everything, there will be residual damage done when the foundation work is complete post-renovation.

I would have probably kept my property management company with over 200 SF homes for the residual income. 

You will need stuff with good residual effect.Good luck and be glad it's not bedbugs!

I told them that they should collect the rents that are due on the 1st and prorate the rents for the first couple days and deposit the residual rent into an escrow account...They want me to collect the rents but I don't think this is a great idea... 

yes anything that produces residue that sticks to the wallS can cause issues.  

First of all, those black streaks while sickeningly high in nicotine (and I mean that literally, you'll get sick with too much exposure) are actually tar residues from tobacco smoke.

I was looking to buy a couple multi families and have a residual rent be income to me whilst living free.

Residual income and building a legacy for my family is the goal!

Sounds like dust or residue in your case.

For example, could $100k be used for delayed maintenance and the residual to pay down the mortgage?