I don't mind paying more upfront, but it's hard to gauge which upgrade choices are going to deliver extra return on the investment... 

I recently bought a duplex and the tenants were month-to-month and I just had to give 30 day notice to vacate and have it delivered to them and that was it.

@Joe Splitrock true...but he is fully vested financially & has agreed to pay for any help I hire so it's going to be a better outcome after-all. 

Additionally, I have customers WAITING for me to deliver the solution vs. building the "solution" (which will likely be incorrect) and TRYING to sell it.  

We have a really good handle on that, so it’s easier to forecast the outcome.

Your best ebt in this situation is to ask for property to be delivered vacant so you can clean it up and put in a tenant that can pay market rent.

Something along the lines of, if landlord is unable to deliver property at Xxx by Xxx, then landlord shall refunding holding fee to perspective tenant, without any further liability to landlord.

I will let y'all know the outcome of this.  

What are some ways to structure this deal so I can under promise and over deliver but also retain a good chunk of equity?

Every household, roughly 13,000 get 1 delivered and then every business in the city (bars,restaurants, doctors offices,gas stations) get a stack of them delivered to hand out for free at the door.