I would advise your friends to 1) notify them that they will not pay for the installment of fences and if they do so, they will do it under your instructions, to avoid breaking HOA regulations, and at their own expense. 2) These don't seem like tenants i would care to have and once this legal battle is taken care of i would not seek to renew the lease.

-ask contractors/do research about making the carport a garage-tons of fences in the back yard "compartmentalizing" each area - knock some down, open up the yard-gas heater is only facing the living room - consider venting it to other side of wall (into hallway)...or maybe when roof gets done install central air and duct through the roof-drywall the rear (detached) laundry room...make it a living/storage space, build cabinets above the washer/dryer (to store laundry supplies) and put cabinets/shelves to advertise to tenants that there is laundry onsite. 

Some cities/counties require dogs to be kept in certain types of fencing or kennels, especially certain breeds.

No offence but I find that hard to believe. 

I did all the demo, tile work (never doing again), install cabinets and hardware, (they were new box cabinets from a wholesale cabinet company), installed finish plumbing, installed appliances, pressure washing of fence, drives, basement walls, framing of washer/dryer walls and a lot of minor things along the way.

No offence intended to you agents out there.

@Robert Gilstrap,  no offence taken,  obviously I haven't given all the details.

Both guys are smart workers and business minded, and have an opportunity to pick up work from the shortage of fence businesses in the area.

No offence taken, I know exactly what you mean. 

(Sorry, no offence intended)...