Stu probably sells more prints and images than anybody else.
There are no guarantees to what you will sell from one event to the next, all depends on the entry list and who has the cash I suppose and also what your photo's come out like, dependant on your location.
You will find you will do more events with no sale than one's with sales. As an official tog for an event you obviously have a better chance of selling than just being 'another' signed on tog.
I have worked with or for Stu on events previously, last years Rally of the Midlands was quite successful with £500+ in sales, according to Stu this year has been dire. I covered the Woodpecker for him last year (as I was going anyway and Stu had injured his leg) and had about £150's worth of sales.
I used to sell pics for myself and got sick of the 24/7 of taking pics/sorting website/sorting proofs/cashing cheques/fetching prints/posting prints/taking pics/sorting website/sorting proofs/cashing cheques/fetching prints/posting prints..................etc etc.. whilst still holding down a 50+ hour a week full time job.
The better half had also had enough of it too.
Selling images is alot easier than having prints done and posting out.
I would look at selling a 900 pixel wide image for about £5 by email. A full sized image would need to be at least 3 times that as they have endless usage of that image.
I now only take photographs for my own usage, for supplying to newspapers that go with my own editorials, or supplied to my clients as part of their PR /website package.
Hope this helps.
Cheers Marcos (macjam off BR)