This eliminates the problem of increasing your debt and damaging your credit score.

Sewer and water in my area is around 10k a unit.

Otherwise, you will likely be copying someone else's false expectations.I have reviewed hundreds of such self-constructed logs, and most of them will not hold water.

@David YoungRecommend you first figure out the property Class you want to invest in, THEN figure out the corresponding location to invest in.Property Class will typically dictate the Class of tenant you get, which greatly IMPACTS rental income stability and property maintenance/damage by tenants.If you apply Class A assumptions to a Class B or C purchase, your expectations won’t be met and it may be a financial disaster.If you buy/renovate a property in Class D area to Class A standards, what quality of tenant will you get?

Umbrella Policies are good, but they are not an asset protection tool, they only cover litigation/damages after you’re already in litigation or found personally liable.

Unfortunately - my current lot for my primary is 1 acre and VERY sloped, and close to a water source (creek), so the county has not even allowed me to permit my downstairs finished basement without an extremely costly renovation to our septic (over $60,000, and that doesn't count demo'ing and replacing our driveway to get to the existing tank and leachfield), and even if I could permit it, it would essentially need to be a treehouse in the redwoods due to the slope (not a bad idea though, I would actually love a livable treehouse on this lot!

This ensures that any payout for damage or liability can be processed more smoothly, and it can help protect your interests if something happens on the property. 

@Alecia Loveless is correct--tenants need access 24/7 to their electric service panel, water and heat, assuming those are individual utilities for each unit. 

As for the first, yes we'd be able to do that (for example, replacing a water heater which is the mechanical that's closest to the end of its useful life).

In case I have to sell or I quit running STRs I wouldn't want to be under water out the gate.