He can also leave any furniture behind and we will clean up.2 – Flexibility to close/move in on date at his convenience.What other suggestions should I make to make my offer better?

From the paint, to the floors, to the kitchen/bath remodel I'm sure it all looked great. 

For example, they get "x" amount of $ for every door knob they switch, "x" amount to change a light fixture, to lay LVP flooring (per sq ft), to hang a door, etc.

Do they sell other flooring?

However, you can expect to recover about 50-55% of your investment when selling the home.Improve curb appeal, which is what you mentioned before, clean up the exterior, add landscaping, and make minor improvements to enhance the property's first impression.

First, clean up your house so you can expand it.

. - along with inconsistent incomeTo be honest this person should not be investing in real estate and focus their time and energy on getting a stable w2 or income and get their credit cleaned up first

what it sounds like you are asking is illegal in many ways, section 8 laws, local laws, duel contract laws that conflict, there always has been also those out there looking to catch you breaking them,  avoid it, dont offer it, dont entertain it, there is leeway up if the tenant meets certain conditions, say need 1 floor rental, if not rent may be inflated over realistic market, which is what rented at not listed at, keeping in mind sec 8 market rents also include utilities paid, you can usually reach by email fastest, they have set chart, heat type, neighborhood etc, more than listings found online

Reno consisted of gutting and replacing the kitchen and bathrooms, replacing the floors, light fixtures, HVAC and roof.

Outfit the space as turnkey for an appropriate business (smoothie shop, dry cleaning substation, etc.) and sell the “business” with a small down payment, receiving a monthly payment for the business payoff + rent/3.