We bought a home built in 1900, insurance water damage coverage is 10% of the dwelling limit. 

So multiple eyes and local expert providing local cost and input on lifespan.Here is an example that has a part that is more expensive in my market than other markets (unlike most parts that are the same everywhere, so in this case your cost should be significantly less due to both cheaper part and cheaper labor): $1600 40 gal water heater installed (this is good price for a plumber, a little high for a handyman) with expected life of 12 years (i have some that go 20 years and some that die in less that 10 years (mostly rheem die in less than 10 years), 12 years is fair life expectation

When looking into it, the basement had water damage that didn't worry us since we knew how to remodel that area ourselves.

In Oceanside, New non-hosted STRs are prohibited outside of the Coastal Zone as of February 10, 2024.Most HOA's do not allow rentals less than 30 days so that is likely not an option unless you find a couple of places on the water that allow it but usually tough to find below $1M. 

Instead, shut off the water to the toilet and place a sign on the door "Art exhibit: Non-functioning bathroom."

The pool needs a new liner, and I do not know if the pumps work because there is no water in the pool.

- Do you want an ocean view, or is proximity to the water or to resort amenities like fine dining or shops most important?

You should look for an "investor-friendly" PM company that knows how it is just dipping your toe into the water of buying a home/condo/townhome.. 

If you have a older home that has never shown signs of foundational issues, and it has a new(er) roof, electric, plumbing, HVAC, hot water heater, etc.

From what I've seen, the days of the $1,000 and $2,500 deductibles for fire, lightening, water damage (not flood), etc. are becoming harder and harder to find.