How to value a Finger Lake Vacation Rental

[J Dono]

I'm a  new investor with two commercial buildings with 10 units. An opportunity at a vacation rental has presented itself and I am looking for advice on evaluating the value of the deal since that's a completely new strategy for me. 

My thought process so far:

-Total cost of the home: $400k translates to $2500/mo with $80,000 down
-price of the home seems in line with comparables in the area
-similar homes on AirBnB and AirD.na go for $400-600/night
-assuming a rate of $420/night it would take 72 nights to cover the mortgage
-a quick availability check on AirBnB makes that seem easily doable. I looked at similar homes and counted up the blocked out dates between now and the end of August and that alone is coming in around 60-70 nights, though I'm not sure if that's a smart way to do it. 
-worst case, I can afford the monthly payments. not that I want to eat them, and yes it would hurt, but it wouldn't kill me.
-the rental is in an area I really like and have vacationed at several times, so I would absolutely use it myself.
-the home is rentable as is, but there are opportunities for value adds (updating kitchen, etc).

I haven't actually seen the place other than online yet and the financing numbers are just from a basic web calculator. Before I really start moving on this, I just want to know if my head is in the right place. 

I know there are costs beyond the mortgage like upkeep/wear-n-tear, property management, marketing, house-keeping. Any good tips on estimating those? 

What are all the obvious things am I missing? 

Thanks!!
"J"