I am not necessarily looking to get rich, but a cushion would be nice. 

There will be unexpected costs that come up, so make sure you give a little cushion in your budgeting for that. 5) Screening- Have a thorough and standardized screening process.

Cash flow on paper gives you a cushion that you won't need to dip into your W2 income if major repairs are needed or maintenance over time.

If this is going to be your first investment, it's important to budget for any necessary repairs or upgrades yourself to ensure a cushion or opt for a different strategy. 

I’m aware California is not the best market, with the restrictions and potential new tax coming up, etc, but we have personal reasons to invest there.With that said, we visited a lot of houses in the San Diego area and saw 2 that seem like a potential fit for us: one is a smaller 3 bedroom but a mile from the beach and the other is a 15-17min drive to the beach, but bigger with 4 bedroom and a little cheaper, which would allow us some cushion to invest on a hot tub or potential pool.

Especially for someone doing it for the first time, there’s just no “forgiveness” in the equation; no “equity cushion”. 

You may end up lopsided on a deal and you need to have the proper planning and cushion to make sure you are not wiping out your entire bank account and starting from zero 

I would agree that it is "normal" to have that cushion and buffer - but yes, errors and mistakes are endemic in the servicing industry unfortunately

It isn't unrealistic at all to expect $15k cash flow from that and that provides a cushion in case of other issues with the long-term rentals.

I think it would be best to have a nice cash cushion prepared before jumping and making an investment.