[quote=paranoid]The case I am looking at: current mello Roos at about $5700 per year. It will last for about 30 years. The payoff now is about $58000. The implied rate is close to 9%. While the current 30 year mortgage is below 4%.[/quote]

hmmm, so over 30 years you’ll be looking at $171k.

meanwhile, you could do a line of credit say at 4%. let’s say you pull a 15 year mortgage at 4% to pay for the MR amount, your payment would be lower, it would be deductible, and it’ll be paid off at half the time or less. let’s say plans change and you end up moving in 15 years, there’s really no loss for you either.