What on a TIL are you expecting to add up?  It is really a pretty a simple form, though it takes some funky algebra to get the numbers.  It mainly just shows the APR, Finance Charge, Amount Financed, and Total of Payments.  Nobody really cares how the lender arrives at the numbers they use - and if anyone did care, they probably wouldn't understand anyway.

In my opinion the TIL is useless.  What they should have is a simple form that shows:

Line #1:  What was the sales price? 
Line #2:  How much did you borrow?
Line #3:  How much did you bring to the closing?
Line #4:  What the transaction actually cost. (#2 + #3 - #1)

I suppose you could make an adjustment for tax prorations and the like.  A refinance would be even easier.  Of course, it really doesn't matter because no body pays any attention to all these disclosures anyway.  They don't care.  They just want to know how much it is going to costs each month.

Best,
Robert A. Franco
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