We do not always get purchase orders for extra work. Sometimes we go ahead with the work and then bill them later. Sometimes this has got us in trouble and we have had a hard time getting the money. We find if we wait for the purchase order it takes an extra day or two and puts the job behind. Also your have to give a firm price to get a purchase order for the extra. Some of the extras are hard to put a firm price onto. Can you get a purchase order for time and material cost basis? If they verbally tell you to go ahead with the extra is that a legally contract? We do a lot of retail stores with tight work schedules. Is they any ideas out there? Anyone do a lot of chain retail stores in the malls etc. Is there any other forums out there more suited to Commercial / Retail Contractors?