Finding the property, negotiating, finding and managing any subs for work he would not do (such as plumbing and electric), purchasing materials, doing quite a bit of the labor. 

I also redid all the plumbing, electrical, and painted the entire place.

A contractor can help yes when it comes to looking at it and telling you how much or what you be looking at if you want to upgrade or fix something visible but you need the inspector to check out the roof AC and plumbing thoroughly despite what it looks like in person I’ve seen mini jacked up ceilings.

Upgraded the roof, plumbing, electrical, waterheater and windows.

I would also check references and make sure the installer is licensed and insured.Roofing has more variables-disappointments- than even plumbing and you want it done right the first time.

Builders, Trades (plumbing, electrical, etc.... )?

I am a plumbing contractor new to Wholesaling, but I am 3 days into my first mailing and am currently seeking buyers to add to my list.

If you're planning on building an ADU or JADU 'yourself', my suggestion is to make sure you have some previous knowledge of construction and also make sure you know good sub-contractors in the following trades:  electrical, plumbing, foundation, roofing, framing, drywall/paint, stucco, tile, cabinetry, flooring, HVAC, concrete, etc.The last thing you want is poor quality work that has to be re-done because a handyman or the wrong tradesman did the work.

New refrigerator, dishwasher, granite counter top and sink, new faucets and plumbing, fully furnished.

Raised foundations tend to be easier to add bathrooms because plumbing can be moved under the house such as from an existing laundry room.