However, San Diego is an extreme case.However rents increase fast in San Diego.  

They've increased the price several times in the last few years. 

The 401k is a valuable asset but its my thought that I can use this asset to further increase my portfolio by putting that money to better use.

Cheap money and low rates produce euphoria, which increases flow of money to an asset, which pushes up the price to uninvestable levels.I think it's going to get worse than better in the short term.Gino

You already mentioned Mid term, which can be a great way to increase cash flow.

The property manager should be involved before you buy any property to give input on due diligence, how to increase income and reduce expenses, and to make repairs or improvements to maximize occupancy.Excellent property management is critical to your success before, during, and when planning to sell or refinance.To your success!

The data points they use made me feel like it got my pricing right and I feel much more confident about what my nightly and seasonal rates are now. 

I am very confident that my STR PM would be able to evict an STR tenant that over stayed their reservation in less than a day and likely in less than a couple/few hours.  

Who cares about lifetime interest costs, except to the extent you can easily lower them (refinance to a lower interest rate) to increase your cashflow.

The first couple is a no-brainer.The second group has too many people, increasing wear-and-tear on the home.