waiting
I think the problem is that while your math to reduce the sales price of the property to account for the higher Mello-Roos is one answer in a stable market, the Piggs here complain because the price of the house is inflated regardless of the M.R. So do you take 50k off of a 700k house or do you take 50k off of the same house when it is priced at 550k. With the price of homes inflated so high and coming down so fast, it is hard to price in M.R.
Also, that is money that will never produce equity for the buyer. I would rather pay 50k more for a house (non-bubble price) because that payment is paying down some principle and building equity. If I spend 300 a month in M.R. it is never going to be recouped.