We have had significant interest from our inner circle but nothing has fully materialized. 

A few thoughts based on your questions:Active vs. passive income for STRs:STR income can often be treated as active if the average guest stay is 7 days or less and you materially participate (which you already do, based on your involvement in cleaning, minor repairs, etc.).

Many of the materials available here on BP were written several years ago in a vastly different market and no longer really apply today.

Depends on how organized you are and how willing you are to deal with the municipalities, sub contractors, material suppliers and mistakes that will inevitably occur.  

After the final video walkthrough, he asked for another $1000 (this is over the $12,000 we already paid) saying he miscalculated the material costs and they were more expensive.

I budgeted about 20k for the material and labor. 

The Airbnb side can qualify under the STR rules if the average stay is under 7 days and you materially participate (your 100+ hours helps with that).

Think about maintenance and turn overs when choosing materials.

find cheaper materials and laborers Did you work with any real estate professionals (agents, lenders, etc.) that you'd recommend to others?

See if they list any law firms that are involved in the sales and contact them to see if there are white papers or other training materials.#3.