Installment sale without interest

[Kea]

I am working on my first installment sale and I want to make sure I am doing this correctly.

In May 2007, my client sold land for $113,000 total -- $25,000 down and $500 per month until paid in full (176 payments). They did not include interest.

Thanks to your help on this board last November (when client informed me of sale), I know to use an imputed interest based on the AFR published by the IRS. In this case it is 4.79%.

I have created an amortization spreadsheet and calculated the present value of the loan to be $63,128.76.

Client purchased land in 2003 and has a total basis of $29,995.

Client paid closing cost @ sale of $785.

In reviewing Pub 537, I see where it discusses Section 1274 vs. 483. Since the sale is for less than $250,000, it is Section 483. It is "unstated interest" not OID. I am not sure however, what difference this makes. (I know a little about OID - took a class about 10 years ago and hoped to never see it again -- even though I like numbers and nitty-gritty math.)

Based on my amortization spreadsheet and the 6 payments the buyer made in 2007, I calculate $1503 went to principal + the $25K down payment, and $1497 went to interest.

I then report the $1497 on Schedule B (buyer name - installment sale)

This is how I am completing Form 6252:

Line 5 $88128.76 (PV 63,128.76 + down pmt 25,000)

Line 6 $0 (client owned land outright)

Line 8 $29,995 (basis)

Line 9 $0 (no depreciation)

Line 11 $785 (atty fee)

Line 21 $26,503 (down pmt 25,000 + portion of pmts that are principal 1503)

Line 26 flows to Schedule D.

Is this correct for a Section 483 transaction? What would have changed if it were Section 1274 (or, do I not want to know?)?

Thanks!