I’m currently in the process of searching for my first property, which I hope to house hack and eventually convert into a long-term rental. 

After sitting vacant for a while I'm entertaining the option of converting to residential units.

Purchase price: $350,000 Cash invested: $10,000 Sale price: $435,000 Primary residence converted to a rental after 2 years.

However, your intent can change and you convert it into your primary residence. 

Purchase price: $325,000 Cash invested: $150,000 This was our first primary home and was converted to rental after living in it for 10 years.

If I understand correctly your siblings goals are to sell their rental properties, use the funds to purchase a primary residence they'll eventually move into, and limit their tax liability correct?

We still need to monitor PH and it uses salt cartridges that the tub converts into chlorine.

Rufo, so you are violating the HOA rules so I don't think they would cover anything if it is the fault of your guests.This will eventually catch up with you and could result in some big fines so maybe think of selling this or converting to a LTR instead.

The first applicant will eventually get tired of his free-loading friends and problems will ensue.

Quote from @Salil Surendran: You MUST convert to landlord insurance.