Breece Veneer & Panel Co., 232 F .2d 319.

Then I would like to start more intensive rehabilitation projects and maybe eventually start investing in solar panels on these buildings as another profit source (and as a marketing strategy).Currently I'm in the learning stage.  

For comparison:Currently working on a 1350sf SFR, needs full perimeter excavation and foundation repair, tear down garage and rebuild (including footings), driveway remove and replace, gut kitchen and 2 bathrooms, minor wall repairs, paint, flooring and light fixtures, new electrical panel, furnace and air conditioning replacement.Total rehab cost is $56,000.I couldn't imagine your property needing more work than this, which leads me to believe that you're contracting your repairs out at a cost that prices you out of the property. 

If there's a loss history, aluminum wiring, electrical panels that are known to be bad, you may pay a lot more.  

wood panelling, shag carpet, etc...   

I'm about to start my first rental property and has solar panels. 

If not, you could use an electric water heater since it doesn't require venting (although would require a 2 poll, 30amp breaker in your panel). 

Keep in mind that's 2 kitchens, at least 2 full baths, 2 electrical panels, 2 HVAC systems, 2 water heaters, etc. 

I want to make it from insulated panels.

Property had been flipped with contractor-grade kitchens a few years prior to purchase...so everything was pretty much turnkey, minus a new electric panel needed to add second washer/dryer hook ups in the basement.