How expensive would it be, and what could it possibly cost in return?

- You MUST have an NNA certification that costs between $65-$170 per year.

Now the tenant will not leave, and we have started the eviction process.This is a clear (and costly) learning experience for me, but does anyone have suggestions about what I can do to fix this situation?

Lots of ARVs, rehab costs, etc are improperly disclosed.A true off market deal is one only YOU know about.

Does anyone have any experience using oil and gas tax deductions (Intangible Drilling Costs: 100% tax deductible during the first year and tangible Drilling Costs: 100% tax deductible) to reduce tax liability against Roth conversions ?   

POH homes can provide a huge lift in NOI depending on rental demographics and home maintenance costs. 

On another side note, I thought what I was charging him was fair as it covered the mortgage and minor repair costs.

If you sell for $772 (let's call it $740 after closing costs), then you'd want to buy a replacement worth at least $740ish in Hawaii. 

If you're house hacking, you can put 5% down + closing costs to get into a property.

The sky is not falling, but I agree if your carrying costs are high and owners did not budget earnings from last year to cover costs of the first slower months (Jan-May) then they are hurting.