Need plumbing advice on rental rehab units

[Danielle Morrow]

Last year I was approached by a gentleman that had purchased a low income 3 family house occupied by a low income disgusting families. Before I took on the building, there was 8 feet of garbage alone in the back yard. Poor guy got sold a bill of goods and got the house for $32,000.00 CASH which in this area is a decent chunk of change. The guys life savings. Anyway - The copper was robbed out of the walls and the basement. As a property manager now I obviously see that I have some plumbing work to do - but I am running into a few problems.

1.) The city actually requires you to have inspectors come in and approve the property - because it has been vacant for 3 years and now lost it's Certificate of Occupancy - I have an idea of what it is going to take, but from the windows to the walls to the fixtures, switches, plumbing - the works needs to be repaired and I need to do the labor to cut back on labor cost. I don't want to hire a contractor if I can do it myself!!!

2.) I am on a budget - An Itty Bitty Budget. I am doing what I can with what I have. I need to find out what the most cost efficient way to do the plumbing. The city hasn't upgraded to PVC yet and demands Copper. Pex, CPVC it's all no good. I am stuck with copper - which obviously will really cost me. I have seen it in the straight lengths and the coil, but should I use? Also what is the best way to go when running... 3/4" ID. or 1/2"ID...Does size matter in regards to each floor (3 total)? Like I said before the original copper was robbed so I have to replace ALL the pipes in the building. :cry:

If anyone has any pointers, I am all ears. I am looking for the most cost efficient ways to do things, but I don't want to keep having to repair stuff either.