Did a photo gig for them taking pictures of equipm...

Did a photo gig for them taking pictures of equipment they are going to purchase. They want all these pictures and serial numbers and such but they don't pay you on time. They say 75.00nip front and 75.00 when you are done. I had to pull teeth to get the first payment. Still awaiting my second payment. Stay away from these guys. They buy stuff for pennies on the dollar and then resell it on EBay without doing anything to it.