I have two Interfire Amps for sale. One is model# IB4700C, the other is IB4900C. I am selling these for a friend and I have no idea what to ask for them!! They are used, but working fine when taken out of the vehicle. I have looked all over the web, and even went to the interfire website, but can't find any info on prices, or where to purchase them online to get an idea. I also have a small Jensen XA2100 2-CH Bridgeable. Can someone please help me. Am wanting to list for sale of ebay, but don't know what they sell for used, to know what to shoot for. I have photos of the items if anyone needs to see them, just let me know. Please help, thank you!!