That looks like a decent 54cm, and be sure it fits him OK. The stem does look too high. If he needs a 56cm to get sized, I'd be interested in the 54cm. Great all-around bike with good paint that will last awhile.

Using just eBay stats, sales of Ironman bikes only, show about 55 sold in the last 18 months, avg price $250 including shipping. The components don't seem to make a lot of difference, but the bidders are more numerous on the Shimano 600-equipped rides. Condition is the big factor.

Plenty have gone unsold, generally because the starting bid is too high. One just went down in flames at $309 twice in the last 30 days, I offered $100 both times, was declined. A frame just crashed yesterday at $50. Several frames have failed to sell over $100.

Beware a seller from Vegas with one like that, he doesn't ship and keeps whatever PayPal can't take back.
I wonder how many times he's done that ? (once to me)

Offer $100 and go up from there. Don't bid against yourself (if there's no counter, seller's either solid firm and will say so, or playing you).
I'd go max of $200. Don't feel bad if you bail at $225, there's plenty of them out there. Not a lot of 54cm.