Batboard

How hard is it to get to mobiles and link them together to be a repeater? Do I have to have radios with 16 pins or will 5 pins work? Do the radios have to be programmed to be repeaters or when hooking them, they already work without programming? I have a P50 radio, I really don't want to take it in to get the crystals changed. Will it work to have the radios/repeater recieve and transmit on the same frequency or will it cause problems with the radio doing the talking? Any info would be appreciated, I am considering making a set-up like this to get more range for my portables. Can I also use a desk mic on the transmitting radio to act as sort of a base? What are the best radios to use, will two M10s work fine?

Start here:

http://www.repeater-builder.com/rbtip/repeater101.html