can reduce capital gain by 15%,,delay 4-10 years or even avoit it after 10 years...3- A $12M commercial building can save up to $600k taxes every year if you can qualify4- Can save up to 28% in expenses every year if you have a maufacture, laboratory, dentist, doctor, storage office, etc...Pretty powerful... 

I am looking at Building a storage unit and rehabbing a house next.

However, besides moving some of my bigger items out of here and into a storage unit near by, renting it as a single family would be much faster and cheaper right now.As I'm typing this, I feel it's really more of a personal decision. 

Not to mention storage, appraisal fee, inspection, HOA apps. 

There are lots out there run by full time professionals: multifamily, commercial, self storage, performing and non-performing note funds......

Would the first floor work for self storage?

Some properties are converted to residential, senior living and multi family, some large big box are becoming storage or office warehouse.

Single family, multi-family, storage units, trailer parks, you name it.

If you get a lender involved (and even if you don't) you should get a couple of things:1) Geo-Tech study - This is for the soil to be stable enough to build on2) Phase 1 Environmental - The person doing this will search title/recorded history for things like buried storage tanks or uses like businesses dealing with hazardous chemicals. 

People who rent a SF also want a basement with a rec room and for storage and a garage.