My contractor was able to get a mechanical, plumbing, electrical, and remodeling for around $2K.

Your energy flows, where your focus goes.

Also realized I didn't answer one of your initial questions:  They took my wife and I on a tour of various properties, one just completed duplex and then two homes that were in the process of rehabbing..both were torn down to the studs and we got to see the electrical, plumbing, drywall and rebuild stages.  

Definitely only get one that is separately metered for water/sewer and electric/gas.Renting a SFH is expensive but is preferred by larger families (2+ kids).  

it's really difficult to tell you every single thing that i look at. i have lots of experience so i can just make offers based on the listing pictures. even if it's just a single picture of the front of the house. that's cause i buy similar houses and know about how much it would cost. but i have a lot of experience, so nothing phases us.in addition, when you have a checklist, the agent will know you are not experienced and will question your ability to close. big things are - kitchen, bath, electrical, roof, concrete.the rest is child's play.good luck.

Electrical and plumbing updates on the outside of walls, other than inside the studs.

I am looking at updating kitchens, baths, plumbing, electric, flooring, painting and windows.

All of our tenants have agreed to that.But an issue that we ran into for this first time is Northern California's utilities company bills electricity annually because we have solar...

Also, you may need to get some bids on how much it would cost to put in the infrastructure (i.e. electrical, gas, plumbing, etc.).

Oh sure, indoor plumbing and electrical and all, but most REI's aren't wanting to become plumbers or electricians, or they'd go to trade school.