The downside is that the nature of project competition means you can get lower quality work and find a disconnect with those you work with since they are looking for more short-term work. 

That could be huge as I am fairly sure the Hawaii short term rental tax is high and it would not surprise me if some people ignore it.

For short term, (Profit / investment), which includes all your holding costs and rehab costs that YOU pay for. 

Long story short, I found a couple who had a wholesale deal that they were looking to offload.

Be careful with the short closing times, sometimes escrow can't get Title or the payoffs (if there's a loan on the property) quick enough. 

I'm about to close on my second property and ideally would like to find short term tenants to get me on my typical June-May rent cycle (I rent to students).

For me the key is evaluating and locking up a contract in short order is the key to getting good deals. 

My short term return estimate relies heavy on return by the value add.  

I read a SF short story not long ago about a senior companion robot, how easy is that to visualize!

Intent is to live in the largest area of the house, rent an already existing basement apartment on short term rental, add a bathroom and kitchenette to two finished rooms in the garage and create a second short term rental, and then put a yurt in the back yard with sole access to another bathroom that'd be installed in the garage as another STR.