Explained it is strictly non smoking (fully furnished property).

I'm thinking at least double the normal rent and probably higher than that, when you think about ROI on your furnishings, utilities, and higher vacancy rates.   

Purchase price: $420,000 Bought this new construction Single Family Home fully furnished and turned it into AirBNB.

My 2nd unit has done pretty well as a 1 BR furnished MTR (only 4 months of experience so far though) and I'm wondering if it makes sense to convert this 3 BR to an additional 2 or 3 bedroom furnished MTR rather than trying to do a long term rental?

The higher end cabins (furnishings) seem to cash flow better and having a hot tub is a must.  

Could one of the units be furnished and rented out on Airbnb or to insurance companies for temp housing or to traveling nurses etc. to generate more revenue?

We are better than most in finding that opportunity/market selection, can furnish tastefully on a budget, and know how to kill it with that customer because we are that customer.

In the contract we signed with the property management company when we first started using them there was a clause that said:"Expenditures for repairs, alterations, decorations or furnishings in excess of Three HundredDollars ($300.00) shall not be made without prior written consent of owner, except in thecase of emergency, or if agent in good faith determines that such expenditures arenecessary to protect the property from damage, to prevent injury to persons or loss of life,or to maintain services to tenants."

Concerning the STR, keep in mind that you will also need capital to furnish the unit.

Three of the six units are operating as furnished units with opportunity to convert the remaining three units in order to dramatically increase revenue.