I'd like to turn it into a year round rental.

Just round math use $200,000.  

There just isn't enough income left to make someone's world go round.  

Now for example, if there was a half-bathroom already there and you just want to put new shower tiles, toilet, vanity, etc. that's one thing (you could probably get away without doing a permit).

Two units are year round, two are mid term.

We are going to check it out this week on a little weekend getaway so hopefully that will give us more clarity too.

Prehung hinged door all the way...get away from bifolds and sliders 

I think STR may be the ticket.

I'd consider starting with letters then perhaps following up with a few rounds of postcards.

Neither of which are really year round of particularly strong.