Oh, and a tiny fiber optic flash light for inspecting the bore.
Any flashlight works, shine it into the breach at an angle, it'll show off the groves. Just not a flashlight that is insanely bright, red light works well.
Actually thats cheap membership.
And you should eventually get your own glasses and ear muffs. Range bag. Cleaning supplies. Probably a multitool or small tool kit. Little mesh bags for the ammo.
For me, it's a universal otis cleaning kit ($50 or so?) with Hoppes #9, CLP, .50 cal ammo can with plastic dividers. And desiccant.
Also, 500 rounds is a bit. If you fire 500 rounds in a month, you're firing A LOT.
The only RECURRING cost with a gun is the ammo, occasionally some more hoppes #9 and CLP, wads and time to both shoot, and clean. My .44 magnum was about $710 or so for the gun. I've probably fired 1000 rounds over a year and that would have cost roughly $400-$500. Already have cleaning supplies since my .40 cal brushes work on all my handguns.
If I had fired >1000 rounds through my .44 magnum, I'd likely need a new hand or something.
The painful guns to fire are the .30 cal guns, that ammo is NOT cheap. I love my Mk14, but it costs so much to shoot regularly. Nearing $1 a round for 168 grain bullets.