So after agonizing over this for a number of days I decided to go with the "Statements provided by your lender." option from 936. At this point it makes the most sense and it didn't take too long to add each monthly balance from my 3 mortgages held during the year and divided that number by 12. The number was actually more favorable that using my interpretation of the "Interest paid divided by interest rate method." Thanks for all the help and I hope someone else might find this useful.
