If it's a single family property that happens to be in a commercial zone, it's one thing and if it's an auto repair shop, that's another (although both would be considered commercial)What type of property are you looking at?

The area crime rate is sky-high and don't put any appliances or mechanicals until you close.

No plumbing is a good thing but you'll still have the other mechanicals that adds up quickly. 

I would say being a mechanic is a better fit to work on RV than being in construction, but any person who is mechanically inclined can do it. 

They are generally higher priced but that may be an option rather than multiple umbrellas.Check with the agent(s) that write your home and auto and the LLCs and see if any of them can do it. 

I'd really like to learn the mechanics, how each party benefits, how each party in the deal gets paid, etc. 

Mechanical still needs called, and once that passes, then we will call for framing.  

My slogan is: finishes sell houses, and mechanics kill deals.  

If you’re not planning on selling/refinancing within the this time I wouldn’t be overly concerned about it....the plumber knows he’ll never win and will never file suit.Google up your state mechanic lien laws, and talk to an attorney if you feel the need.

Local (on device) storage that later syncs when web access is regained would be a slick solution.Robust backups - both online/continuous backup plus the ability to dump a snapshot of data to an external hard drive.Easy access via search to contact details.What deal(s) they're a candidate for.Ability to text through the app.When responding via email, text or phone, auto suggest a follow-up task with a drop down for when to make contact next.Calendar that syncs to your smart phone.Ability to schedule appointments with fields for location and notes for the meeting.