Clean air in suburbs.

You can even sweeten the pot by telling them they don't have to clean, and you will hand them their deposit on the day of move-out after a 10-minute inspection to verify there are no damages. 

This house was very nice and clean (build later 1980) My tenant recently claimed there is mold on 1fl (it is like basement as there is no window, it is next to garage) When i see, the mold is not only one area but it seems widely spread on the ground floor (laundry room, wall, celiling etc) Since it is OOO investment, it is not easy to deal with mold issue.

This way there will no be loose ends and title transfer will be clean, you wont even have to issue a quit claim deed.

To do a clean BRRRR in today's interest rate and highly competitive environment is very difficult.

It is difficult to maintain, it scratches, it warps, it stains, it needs to be cleaned with cleaners made for wood floors, pets tear it up, it transfers noise, it shows wear patterns, etc. 

They keep the home clean, pay rent a week early, and I haven't been called out to fix a single issue.

I did and told them that if they don't have a signed lease and deposit, it isn't rented.One month seems to be normal with PM as they have a number of units turn over at the same time and don't show them until the place is vacant and cleaned. 

I was thinking of providing cleaning, a full gym, personalized workout plans, mealprep services; something like that.

I recommend you use an attorney to ensure the contract is clean and you are protected.