I've done a fair bit of research (online) for what to look out for and what to avoid when talking with the New Construction Sellers agent.I have zero experience in dealing and negotiating NEW construction deals though.  

I’m thinking about providing a cleaning service and lawn care service with no choice, to ensure the property stays up to par.

I suggest you develop a fairly detailed scope of responsibilities for that PM, including how often you expect him to be there and exactly what kind of interactions, inspections, reporting and other activities & responsibilities you expect of him. 

I promised to not make the amount public but I'll say that it was more than fair for me.

What advice would you give a new investor like myself and others to ensure we're successful?

I'm looking for BRRRR opportunity in a fairly area where there is a great PM. 

Take the time to create a proactive asset management strategy that will allow you to keep your finger on the pulse of your park performance, and to ensure that you are constantly moving the needle toward the goal of each park.

@Ray Harrell it’s not that they have to for the sale to proceed but the buyer has them sign it to ensure the seller is not pulling a fast one.

I live in Spokane, WA and rent prices are fairly cheap.

Rehabs are a fairly easy and low risk value add.