Adam pretty much nailed it down. You order the chassis for $303 and then each module costs $199. They ship them seperately no matter how many you get for cost reasons. Look at my photo bucket under my sig and you will see 3 amp modules on the table before I installed them. It takes about 5 minutes a module to install so dont worry about that. You have to call to get anything less than 7 modules, they wont do it over the internet.
The 12 v trigger is no big deal, it's just kind of funny that they did it this way but all you need is a 2 dollar cable from the Rat Shack and it works great.