The biggest questions are about all the little stuff like common area electricity, cleaning and constantly fixing the pool, mowing, irrigation, manager's pay, maintenance crew, exterminator, turn-over,  make-ready etc etc  I am building these apartments in Texas, just north of Houston (its underway and some are done and moved in to)  20- 750 sf one bedrooms, 8- 1120 sf 2 bedroom (2 baths)28- 1930 sf 4 bedrooms (4 baths) I have to fix the full size washers and dryers after the first yearWifi (8 modems with 24 access points) one account per modem that's $80 times 8little bitty managers officeshop for storage and partsdecent saltwater pool but no hot tub, pool has sand filterlots of good outdoor lighting over the 4.5 acresno outdoor stairways and no balconies,Keep in mind there are brand spanken new, one bedrooms are done and occupied, starting the others in a few more weeks after I submit for a loan.

I have come across a house that has the incoming electrical service line lying on top of the roof of the detached garage.

I’ve pretty much fixed everything up already;  the roof, new walls, new electric, and HVAC.

Tenants pay for their own electricity otherwise.

My dad is an electrical contractor, so could use his help for semantics, but my main ?

While those resources are great, an even better approach is having someone physically be at your job site showing you the best way they have found to do a specific task like: cabinets, baseboard, windows, doors, plumbing, electrical...

New mechanical systems (HVAC, plumbing, electrical) would cost at least that much on their own.

While certainly not the primary or only consideration, a good name is important.Pick a name that is: short, easy to pronounce (you're going to be spelling it out for the gas company, the electric company, and tenants)available in the state where you will register the companynot already identified with a national well known company, where the domain name is available for a reasonable price (you don't want users to have to type a long convoluted name for the url address) It's REALLY not to early to have a lawyer working on the OPERATING AGREEMENT which will define the legal agreement between members and the buyout provisions in the event things don't work out.

Have the plumbing and electrical been updated in the last 30yrs?  

With this property the owner pays all utilities besides electric.