It is just the act of getting the big tanks down there and the old ones out, and the fear of having one leak and cause havoc without anyone knowing then having to deal with that liability.The biggest problem here is trying to figure out how to charge the tenants, etc. 

For instance, if you have 50 residential units, with 50 roofs, 150 toilets, 50 hot water tanks, etc. you have a huge liability at any given moment where nearly all of the repair and maintenance expense is on you.

If not, I pass.The first time you get a $600 water bill for one month from a single unit because the tenant "forgot to tell me about the leaking toilet" will help you understand why. 

The crippled man, who was lowered down through the roof while Jesus was teaching.

The metal roof is just about done in this photo.

The cubic foot limit is an interesting one as you could have a pretty dramatic effect on that quantity by manipulating floor to floor heights and roof pitches, seems as though it would encourage more cramped spaces to get the building in under the limit. 

Epic Roofing and Exteriors does great work.

You can assume some percentage of them will have foundation problems, system problems, roof leaks, etc.- Significant title risks.

Leveling, plumbing, new roof, no central air and heat.

What's the condition of the roof, water heaters, and furnace/boilers?