sentences:  Also, in a period and place where painting was a business, and work was generally negotiated by contract, there is both direct and indirect evidence that he was professionally unreliable, though apparently his outstanding talent made patrons willing to take the risk.One contract (discussed below) contained a clause providing for the excommunication of the painter in the event of unsatisfactory performance.Commissions were often undertaken by Bermejo in collaboration with inferior local painters, possibly because of guild restrictions.