I'm not 100% privied to the exact rules. Our GM, the infamous MadCapellan, created a simplifed system based on Economic Points (EPs) as opposed to C-bills or what have you. EPs roughly equate to a ton of equipment. So in most instances, a 75 ton 'Mech, costs 75 EPs.
The actual campaign started at the beginning of the Jihad, while MadCapellan lived elsewhere. Hey ended up becoming house mercenaries for the Capellans (no surprise) and finished up Sovereign Justice. When he moved, he got a new group together, starting at Operation: Thunderstrike.
Those of us just joining (over a year and a half ago) started with 4 'Mechs totaling 275 tons (EPs). From there, we are able to grow our forces through purchases or salvage. Most repairs of damaged equipment are free. Replacing weapons and armor costs the tonnage value in EPs.
Green pilots cost 5 EPs and regular pilots cost 50. However, with regular pilots, they come with a randomly determined 'Mech. I've gotten a Commado this way. Another guy got an Atlas. It's a pretty good deal, but you can get shafted occasionally. But generally, its pretty fun to make that roll.
The EPs we gain from missions are based off of our completion of mission objectives and a function of the value of the units we brought into the mission. The more value at risk, the more EPs you can gain. Every mission, you have to pay upkeep on the units on your list, regardless if they are used or not. Auxilary staff, such as techs and other non-combat personnel's upkeep cost is rolled into the individual 'Mechs upkeep to simplify that process. Additionally, everytime we change planets, we have to pay a transportation fee, which is why we're starting to buy our own dropships.
For pilot experience, you get 1 EXP for going on the mission. At the end of the mission, the OpFor vote for one pilot to get a bonus point. Then the group at large picks a team MVP for another extra point. If you OpFor, all of your forces (all units) get 1 EXP, as they've been deemed to have spent the time training.
So yeah, that's the basics. As of right now, MadCapellan determines our missions and route, since we are under the command of the CCAF. Eventually, after Thunderstrike is complete, we might have a sitdown and plan out our next move. But we are at least a handful of months away from that. I'll see if MadCap will give me some specifics on how he determines EPs and the like. I've been bugging him, but between his real job, his writing for Catalyst, and some of his other hobbies completely flushing out his campaign management system and putting it on paper (word file) is not in his priority list I'm sure.
Anyway, I hope I've given you a decent idea of the system. I hope you enjoy following along in our adventures. Feel free to comment here or on the blog. Thanks for showing interest!!!!