Any recommended agents or PM who can rent out my other unit? 

Grading - put a spirit level on the ground away from the house.

I considered SFH where I'd rent out all the rooms and keep one to myself, but this seems risky since I'll realistically be away for months at a time and couldn't manage the unit/other tenants.Then I came across some listings that appear to be hotel rooms for sale, with basically the facilities I need (a bed, toilet, kitchen), a price point I can handle (270-500k$, I'd do 20% down), and fairly high HOAs (~1500$/m?).

Investment Info:Small multi-family (2-4 units) private money loan investment.

Usually the programs are only available on one unit properties such as single family residences, condos, planned unit development (PUD) and townhouses. 

Working with KW you will likely get a lot of high-level education.

I am looking at a property here in FL that is listed as a single family for 470k but is functionally a triplex (3/2 house with a guest house in back that has 2 units, one is a 1/1 and the other is a studio, both units in guesthouse have kitchens).

I've also learned to have a healthy level of skepticism when someone is TOO eager to move fwd quickly after/during a first meeting.

All we really know is the starting NOI and the level at which we can increase it annually.

At certain times of the year in the spot your house is on the water level may rise up from below.