Cool, sounds like you're on the right track and it's really nice to have (and support) a local community. I just like to be honest about these big builds or trying to be competitive. A lot of people get into this thinking that sort of thing is a one and done investment of time/money which is rarely the case. I can assure you, if you save receipts as you go your build will be over budget regardless of how much you thought you planned, and something will break that you didn't expect or you'll find some unexpected weak link that will need upgrade.
Finally, if your goal is to get loud and be even somewhat competitive you should really own an SPL meter or at least make friends with someone who owns one and is willing to let you use theirs whenever.