BUT I am ready to ship him some plumbing supplies. 

Also, consider trade schools that would teach you HVAC, electrical or plumbing work or even carpentry. 

Without knowing the full scope of work required (framing, plumbing, electrical, HVAC, etc.) it's impossible to even compare or comment on those bids you received.  

So be sure that making this into a multi unit is actually going to be financially beneficial.If it's a gut rehab, you definitely want to split the plumbing/electrical/HVAC so that everyone pays their own utilities.

So I'd want to check the condition as a starting point: I'd pass unless the plumbing and electrical has all been recently updated in addition to that furnace. 

Hello Expert,
                 I am a newbie and need some recommendation for some good contractors who can help with the fixes for my new in property in Mesa area. Please feel free to DM as well. 

Moving walls, rewiring entire house, adding bathrooms, relaying out kitchens including new plumbing runs, etc.

But recently there were some plumbing problems reported by the new tenant that have necessitated a plumber.

A house that has a straight roof line and good bones is hard for me to tear down.If the plumbing and roof is needing replaced, then I would  consider tearing it down.my suggestion is get 3 top real estate agents to give you their advise.Your in a great position to do several options!

The girls are harder on the property than the guys (plumbing) and also more high maintenance.