Does each unit have a separate gas and electric meter? 

I recently had an electrical panel that needed to be replaced that the inspector missed which ended up being $1,100.

If it's your building, and you want to clean it up, clean all of it up.

I started with house hacking and then purchased rentals that were clean BRRRRs.

Those guys aren't cleaning that crap up. 

I even added the electric bill showing them its in my name.  

It has separate gas, electric, two hot water heaters, etc. 

What you pay with labor will depend on if for instance one of my units still has a good pad and tack and strip then I just pay for carpet and installation cost.What you will pay will also depend on how much you are installing at one time.I don't like Berber for rentals.The design of the loop once it starts unraveling it can unwind pretty good an dis harder to get certain stains and pet stuff out of it.With carpet you want a Nylon carpet even if the cheaper version.Some carpet guys will try to sell you the rubber composite carpet stuff which is the really cheap stuff so it will stand up to tenant abuse.The problem is it can only be cleaned usually up to one time and then you need to replace it again.So I would rather get a cheaper nylon that can be re-cleaned many times over after installation for an additional .10 to .15 a sq ft extra than the super cheap stuff I will have to replace again.If you get 1 sq ft for carpet,pad,tack and strip,and labor install and it is Nylon you are getting one heck of a deal.Even at a carpet place usually you are at .40 to .50 for the pad and .50 to .60 for a cheap carpet.Then you have to do material to install and labor.I have seen sometimes if you have to do a small area you can pick up quality remnant pieces for real cheap and hit that type of number or buy in bulk.

Plumbing drains, water, and electrical were all VERY easy to run. 

All of a sudden, EVERY application is coming back squeaky clean despite criminal records, misdemeanors, felonies, evictions that can be found with a public records search.