But now I'm thinking I should have done better because I'm getting just over 10% ROE.  

One benefit of an HOA having established rules is that for any changes to be made requires a 2/3rds majority vote of the residents to overturn rules.  

One or the other could possibly overturn the sale. 

IN MD the former owner has a statutory right to challenge within 30 days and deliberate fraud must be proved to overturn after a year. 

Or it could be that the superior quality and location of the lower-producing property simply merits the lower ROI or ROE -- which, if you analyze it, is not exactly horrible.Let's say the 1% income property chews up half its rent in expenses as many here will tell you it will.

Any decent judge would overturn that deposit deduction.

I do know the importance of the arbitrage on the ROE.

Many tax deed states have allowances for the sale to be overturned if it was held improperly (without proper notice, or if there was a mistake, etc.), so regular title insurance isn't available.

You should sell before you lose the capital gains exclusion and put that money into something else with a better ROE.

They are quite common in FL Foreclosures....never seen one actually denied/overturned.