You did well: there is never a rule against one-off contract. I can assure you the CEO has a one-off contract, and that lawyer has a one-off contract, at the very least :D
Those are great points. I didn't think about it at the time. Since they were pushing me hard to sign a contract that for once literally blocked most of the companies in the cs speciality area I mostly have worked in, it gave me enough courage to say no. Barely ;-)
