I sold a used Stringway/Laserfibre ML200TT in the past for $450. But they don't come up very often. $500 for a Revo 4k is i bit on the high side.
I agree with mad dog1, you don't have to buy Xuron at $20 a piece. Cresent sells a set of Xcelite pliers and cutters at Home Depot for $15, or buy the Xcelite individually.
I highly recommend a starting clamp, but the prices have gone up over the years. Eagnas used to sell a starting clamp for $16, but has since raised the price to $26. There is a great Tools thread on TT, I suggest you read it.
Machines: Gamma 6004 2-point w/ Wise 2086 & Babolat Sensor Dual