In nearly every case, the IRR continues to decrease the longer the property is held even though the cash flow is increasing.

Subtract depreciation, explained here:https://www.biggerpockets.com/forums/51/topics/1121063-expla...Because of Step 2, depreciation, many cash-flowing rentals end up showing $0 net profit, resulting in no tax increase and sometimes in tax decrease.

The multi-family market has remained strong, and if rates decrease I think we see more buyers in the market irregardless of property tax increases.

Your price range is very doable in the San Antonio market as prices in TX have continued to decrease substantially over the past quarter.

Can you consolidate the portfolio (sell a few properties) and decrease your debt? 

And lastly, I search FunishedFinder listings nearby, find comparable properties, and track the listed rent for a few months (does it increase, decrease?).

Prime rate runs ~3% higher than the Fed rate but as others shared unlike residential mortgages with the prime rate there is a direct correlation and as the Fed rate decreases so does the prime rate.  

The sponsors’ goals included “protecting naturally occurring affordable housing” from teardowns, decreasing “gentrification” and lowering property taxes for homeowners.

If the CO market is doing well for sure investors doing well too, if not, your equity may be decreasing as well. 

As a result, a mixture of high taxes and decreasing job prospects are making rental properties less profitable and more risky, never a great combination.