Paint and fans.

-tenant service recommendations... i.e. list of internet providers, utility contacts for turnover, and renters insurance providers, local amenities among other things-house rules-legal & insurance contacts for when stuff hits the fan.

We will not talk of this but planned to further clean after they finish by ourselves every 2 or 3 cleaning of this cleaning people, such as corners, along the wall, under beds, on the fan....

Use a fan or a portable AC unit if the reason for the open windows is that it is too hot.Trying to chase all cracks and sealing off your unit in a 1980s building will be mission impossible.

(I'm obviously not a huge hotel fan and never have been...) 

Also, I would like to update a 1st floor bathroom & install a ceiling fan w/lights in the kitchen, maybe update all the electrical outlets to white.... so recommendations would be greatly appreciated. 

In a lot of the HOA they are not fans of rentals.

I'm a huge fan of paid mentorship or coaching in almost any field, especially REI.

One option I am not a big fan of that wasn't mentioned is cross collateralization.

I'm a fan of marketplace when I have the time.