The property is in great condition, it will definitely appraise for market value along with current comps. 

A $1million home will have $276,000 in value increase after 5 years (using that same 5% appreciation per year).

Increasing unit number or using less conservative, or increasing rent numbers or lowering vacancy rate could be close to a 6% cap rate.The area is known as a tourist destination, is geographically constrained, has a massive housing crisis and isn’t expected to ever build enough housing to meet demand.

If you are asking what the cost of rehab is, well that depends on the condition.

It's important to carefully research and evaluate the local market conditions before making any investment decisions.

Any increase in revenue will not be attributed to the photos by hosts.

I would probably continue to save so you can increase your budget

Demand for short-term rentals is based on emotions, the allure of this view or that amenity or this undefined "feel" or "design" of a place.I'd love a pamphlet that says simply, "Hot tubs increase gross annual revenue by $22,000."

And, to follow the lead of a newbie will surely lead you to increase risk and liability. 

You should know the target investment area well enough to quickly recognize actual deals versus those that are not going to be profitable.You should then have a team in place that can quickly validate the condition of the property and give a decently accurate estimate of repairs.