Looking good! I used particle board for my build too (for the same reason as you...lol), and I see some of the same issues in yours (screws damaging corners). I ended up going to a friend's house who has an entire woodworking shop in his garage to finish my build. The key is to pre-drill all screw holes, and to make them look nice, use a countersinking drill bit so that it leaves a space in the wood for the head of the screw.
As for the finish of the box, I stumbled across a thread somewhere that said to use spray on truck bed liner
to give particle board a nice professional looking finish. I used it on mine and it does improve the aesthetics of the box considerably. The key is to lay down a good coating of primer so you're not wasting a bunch of the bed liner with the wood absorbing it all.
If you figure out how/where to get a plastic housing made cost effectively, please share.
I have a buddy who does a lot of work with aluminum and I'm going to see what kind of cost I'd be looking at to rebuild my box out of aluminum. The big issue then is making sure the wifi signal can make it out of the aluminum enclosure far enough to be usable.


