>Thanks Rich. I charge them $100 per year as support fees. So far in last two years, they have spent $120 for modifications. They want to maintain the software themselves and make some modifications. I think it sound cheap to sell it for around $200, don't you think ???

Since I've always worked in the corporate environment, I can't comment intelligently on what the value should be.

OTOH, I've rarely let ignorance get in the way of offering an opinion.

Doesn't seem to me the dollars involved justify your keeping support. I'd try to negotiate up from their offer and take whatever they are eventually willing to pay. (Maybe that's why I've stayed a corporate developer????)