My cash flow calculation is based on accurate and ideally conservative underwriting that includes all expenses including maintenance/cap ex, vacancy, PITI, book keeping, asset protection, misc.I would never bother with a unit for pure investment that was projecting anywhere near as little as $300/month total return. 

An LLC is useful for two things: anonymity and legal protection.

@Tar-U-Way Bright Using your LLC for real estate ventures offers legal protection and tax benefits.

Will you not renew them and suffer all of the vacancy/turnover costs?

We plan to remove them all to protect from tax increases on our current primary, but I am afraid that now that the other properties won't have homesteads, we may see skyrocketing tax bills and it will eat into already small cash flow from rental income.Does anyone have advice for how to handle this situation other than just increasing rent?

Only government and insurance companies insist on not letting go of mail.It's good asset protection.

No, only after missing significant payments then you could suffer a forced sale.     

I’d like to be protected if it takes longer than 60 days to sell a spec.

I use a channel manager (OR) and it has damage protection built in.

;-) Your comments are refreshing for me, as a fund manager, to remind me that we can't let subscriber communications suffer in the midst of a major economic disruption.