Additionally, how many calls does it typically take you to successfully close a deal using this approach?

In any pricing software or even inside of the OTA's themselves you can offer weekly discount on stays 7+ nights and additional savings for 28+ nights. 

In addition, you would need enough working capital to pay for insurance (which will be going up a LOT in Los Angeles) and to pay for property taxes.Don't buy this unless you have substantial resources and a cash cushion to keep yourself safe.

In addition to that, building your network is key.

If you do have to move because of a job, you would be safest (in my opinion, i am not giving legal advice or financial advice), i would sell that property to ensure that you did not just purchase with the goal of moving out early and taking advantage of lower rates and lower down payments for purchasing your home as a primary residence. 

Section 8 would tend to carry higher repair and as a result, additional vacancy.OP’s definition of cash flow is rent minus piti.  

If your focus is on minimizing risk and ensuring consistent cash flow, your current strategy works.

Framing your position as fair such as explaining the difficulty of finding renters during off-peak months - might help maintain a positive relationship and reduce risks of property damage.Prepare for What’s NextEven if the tenant moves out early, ensure you’re protected.

These are professionals with additional training and a stricter code of ethics.

Additionally, I know the Waivo product for STR covers intentional and accidental damages.