Purchasing used Cobra gear

[darkpyro]

I currently own an 18M and 18R. I'm looking to expand. Does anyone have thoughts or suggestions on purchasing used equipment? I know there is a difference in hardware versions (A vs B). I'm looking to get additional firing modules, 18R2 and audio box. Have seen a few for sale but unsure if there is something that I should be looking out for. This was first year of using Cobra so it's all a bit new to me.

Thanks

[displayfireworks1]

Buy more new Cobra equipment. Everyone selling used wants 20 dollars less than new. Please don't do post any unapproved buying or selling on these forums. Wait for the next Cobra sale.