.- Internal Rate of return of ~15% and cap rate of 5.5%.

New siding(added immediate curb appeal), removed old popcorn ceiling, re mudded walls, painted interior, cleaned, cleaned and then cleaned some more, added front deck, landscaped front & backyard, What was the outcome?

Typically they are high net worth individuals or groups (sometimes international) willing to buy something all cash and accept a minimal COC return for nice building w/ little maintenance etc.

I like to concentrate on the interior items to make the place functional but make a list of all the exterior items that need attention as well.

My wife (realtor) and I will be handing architect/interior design and the sale of the property. 

That said, we're both motivated and my partner particularly has a knack for interior design, so we're not averse to a property improvement play.Is house hacking a realistic option for us?

IRR is Internal Rate of Return. 

The house needed flooring, interior paint, some exterior paint.

Each one has their own internal rules.  

An international tax specialist would be able to add more.