A rule of thumb is 3 x your turnover + profit. + are you selling the property your trading from, do you own the gear, have you cleared the deck IE. have you agreed a redunancy package with your workforce. Clients on the books is an attraction to a prospective buyer and may add to the value of your company but at the same time it's a gamble for them and they will weigh up their payment record regarding their ability to pay on time. All of the above is taken into consideration by a prospective buyer, talk to your accountant and see can he put a value on the company and take it from there. Hope you have a good outcome.