But I spend far more on ammo than I do on the weapon. Keep that in mind.
^ This. You NEED to invest in a reloading kit ASAP once your rifle is assembled. A basic reloading kit can be assembled for under $200 with all new parts, if you are willing to use Lee Precision equipment (I do!). That will dramatically reduce the cost of ammo if you are willing to buy components in bulk. If you want plinking ammo, then surplus pulled powder is the way to go. Buy components in bulk. Did I mention that you should buy components in bulk?
If you are so inclined, for your SHTF/Zombie Apocalypse stash, buy an 8lb jug of powder, 2k bullets, 2k primers, and 2k once-fired Lake City brass.
Or, look around for someone willing to let you borrow action blocks, an armorers wrench and a few punches for a day when you have all the parts. Dang, get all the parts and I'll mail you mine when you're ready. Just be sure to save that return address! I'm sure there's bound to be someone closer than Ohio, though.
Honestly, you don't even need ANY special tools to do an AR, if you are careful. several (many!) layers of masking tape with a bit of duct tape over it, and a pair of vice grips works just as well as a stock wrench. Those same vice grips with more masking tape can take the place of a roll-pin punch for the bolt release roll pin (and makes it harder to break off the fragile metal that pin goes into). Regular steel punches can be used to do the rest of the pins if you are careful and use masking tape covered in duct tape.to protect the surrounding metal. The vice block is nice, but not mandatory if you have a friend to hold onto things, or some scrap wood lying around to build a jig. I assembled my first AR lower with no special tools.
Expect to pay about $400 new for the .22 upper, and it doesn't really make sense to buy that as separate pieces. When you build your centerfire upper, you can shop around for exactly the parts you want, or you can buy a quality complete carbine upper for around $500.
I personally like the 1/8 Melonite Polygonal 16" for general kicking-around carbine and light target shooting out to 300 meters. Mine is a tad over MOA when I do my part, and I'm using crappy bulk FMJ bullets in my handloads. I'm hoping to get sub-MOA with some Z-max bullets I just acquired. I got that upper at a local California shop that specializes in black rifles for $499. You can find cheaper lowers, especially if you don't mind a slick-top style upper and no-name parts. For a SHTF rifle, though, I'd rather have a little bit more rifle than I am ever likely to need, and 10 years from now, I'm not going to regret that I skimped $100 on my upper.
Save up and buy once. Find economies (like reloading, not buying special tools, starting with a .22 upper) early on, and put those savings towards things you want longer-term (reloading component stash, magazines, magazine pouches, low-profile rifle case, rails/magpul MOE handguard, light mount, sling, chest rig, TA-31/RCO ACOG, Eotech, Aimpoint & magnifier, bipod, forward pistolgrip, spare bolt, spare lower parts kit, steel targets, etc...)
