prior to purchasing the carwash I was part owner of a mobile auto detailing company that we operated out of a 2800sqft warehouse.

I can't decide between exploring a 203K loan or getting into flipping mobile homes.

there are numerous commercial RE options such as storage units, mobile home parks, industrial, office, NNN, etc.  

STR in those areas do well year round because of fall colors and ski resorts and snow mobiling if they are on a lake, but on the flip side you are paying significant more because they serve dual purpose.  

Tell them to buy a portable version?

I applied for a spot in a mobile home park and was rejected.

Hence, a mobilization fee before the crew and materials show up on the job.A flipper who wants the GC to fund their job will always be paying full retail. 

Tiny homes and ADU's generally face a lot of challenges as they are a disruptor to the RV and mobile home markets.

It wasn't too long ago (about 7 years now) I was flipping my first mobile home trying to get some cash together!

We have android phones and the mobile app works fine.