2nd hand pricing and advice (I'm buying not selling)

[kybo]

Hi,

Sorry if this type of post is frowned upon but it's not a selling ploy, I assure you (if I had the 100-400 I wouldn't be selling it!!). A work colleague has moved from Canon to Sony and hasn't used his Canon equipment in over a year now and has decided to part company.

I am interested in a couple of items myself and wondered if you 'peeps in the know' could value them. Yes I have googled and gone on eBay (pricing varies considerably) but I thought, by posting on here, I could kill 3 birds...

...I get good, example figures, some of you might be interested in some of the gear - I can pass your offers on and I need some advice on some of the gear (so thought prudent to get all from one place).

Anyways:

Canon EOS20D (body only)
Canon 75-300 USM2
Canon 100-400 IS
Canon 28-135 IS
Sigma 17-35 F2.8-4.5
(that's all the info he's given me)


I know I can't afford the 100-400 IS but wondered if the 75-300 would be any good for Motorsport? Also, would the 20D be a marked improvement/upgrade over the 350D I've got? Is the Sigma a good lens?

Thanks in advance,
Scott

PS - he does look after his gear so everything will be in good nick.