If your hold period is short, it may not make sense to take bonus depreciation.BENEFIT - Clearly additional depreciation is the benefit, but only if you can use it. 

I am curious though, in hindsight, how does an investment in STR in Hawaii in 2012 would compare with other markets over this period of time despite all the regulation headwinds?

Hop on Airbnb and scan nearby properties of similar size to get a feel for what they offer at the price points charged.

I generally try to put my October through January lease starts on 18 month initial terms to better align with more favorable leasing periods when the units come back to market.

When you have enough data over a long period of time, there should be enough to generate a useful score. 3.

Shop LTV (or cLTV which is combined Loan To Value, basically your first mortgage and 2nd mortgage combined loan to value), rates, payment terms, time to close,  and draw period (how long you can go into and out of your heloc). 

Whereas with an STR, even with clear english detailing any issues up front, is often booked on a whim with an overload of information digested in a short period of time.

Period!

Excluding the periods of “tulip bulb” irrational exuberance, a property must produce enough of a risk adjusted return to satisfy both the ROI demands of the “limited partners”, and the income/time requirements of the sponsor.  

Your issue more so is the seasoning period for the refinance is what it sounds like.