Deductions & credits

Thank you Renee - my prior response was to Jason's comment above.

One point of clarification for your response to a)  - so I should add the 3 box 1 amounts, less the adjustment for the interest on the increased principal?  Will it matter that if I use the original lender this year, but use the new latest lender next year? Just trying to understand the rationale of using the original lender if there have been two additional lenders since.

Thanks!!