I used to shoot Balcar before switching to Profoto.
Balcar is excellent lighting. I have a P4 pack and a number of heads that I'm selling.
I'm probably keeping one of my two Concept P4 packs however, but I might be willing to sell one of them (they are rather rare digital packs that have 4 lighthead connections and each channel is independently variable within 1/10th stop increments (Concept packs cost just over $2K new).
I have quite a few P4 heads also.

If you're a Balcar user, you know what these are and how hard they are to get any more.

Not sure on pricing, but I'm thinking the smaller heads will be in the range of $250-350 obo per
The P4 pack will be in the range of $500-600 obo

The concept pack will probably be near $1,000 obo

BTW: For you Paul Buff users; Balcar is the top end system that PCB borrowed their lighthead mount from. So, this is an opportunity to step up your lighting while still being able to use all your accessories.