I'm not sure about the "buy points" aspect, this is something we didnt do with our mortgage. We have a 30 year fixed mortgage so the interest rate doesnt go up but the monthly amount can go up due to increase in property taxes, home owners insurance increases, which ours did for first time in several years. Only went up $12 a month.

From our house payments amounts are taken out for our home owners insurance, property taxes (monthly pro-rated) which are then put into escrow account, at the end of the year they pay all the amounts due for us.

All those upfront costs, can be deducted from income taxes.