This is a cheap temporary solution so the tenant doesnt drive you crazy in the meantime. our windows slide left to right not up and down so there is nothing to hold a window unit in place.. it would be dangerous to put a window unit..his apartment runs length wise and if he did open the window in the front of the apartment ( living room dining room) and his bedroom in the back it would cause cross ventilation but he refuses to open the windows for safety reasons.. we are in a nice area and he is on the second floor.. our living room dining room have ceiling fans and we gave them 2 large stand up rotating fans.. the lease does say there is no compensation for a temporary lose of heat or a/c.. so would that still leave me liable for his hotel bill?

None of the tenants were willing to pay $30 extra per month for exclusive driveway use, so I put up a weekly schedule for the carport to rotate between two units-monthly would work also.  

I house rotating doctors, visiting researchers and medical students.

Right now, it's a losing fight that only creates problems and a strained relationship, but based on how your tenant is acting, I suspect this isn't the last problem you're going to have with them.While I don't speak from personal experience here, my father has dealt with tenants like this in the past and this is how he has successfully handled it.

We chose these students because they must go through background checks and drug tests for school since they'll be placed in hospital and clinic settings for their rotations.  

It may put a huge financial strain on the owner to try to cover the principal payments on two properties in order to get appreciation at some unknown future date.

as a general rule I never rent to friends, familk or Co workers as it Can complicate the landlord renter relationship and strains the work relationship.

Your Heloc doesn't pay you interest, in fact it costs you interest, not good at times of financial strains.

Make sure any agreement is in writing so that you don't have a strained relationship down the road. 

And if you're doing any electrical work don't forget the bottle of sparks, decepticons, autobots, and a 360 degree motorized rotating ladder to screw in light bulbs.