This would be better than learning a large purchase may not help you tax-wise come filing time. 

This is my first post on BP after watching so many videos.

I will be doing a pretty large renovation in one of the units, and mostly cosmetic reno in another unit, so i'm wondering what the best way to go about dealing with any potential lead issues in this case.

I will cash out, refinance the new house, and pay the renovation loan.

We agreed to, but we countered with a 60 - 90 day closing because we are relocating from out of state.

How bad is this deal?

But I’ll throw out a different approach.  

Two out of the four have been renovated and are currently rented. 

Two out of the four have been renovated and are currently rented.House 1: Before purchase the tenant was paying $900/month.

Sounds like you took the first step by making this post.