Cooking a $10 bird in $30 worth of oil doesn't make a lot of sense (neither does taking a $1,200 shotgun and shooting an $8 duck).
You can reuse the oil (you think Mickey D's throws their oil out after every batch?).
I've fried a dozen or more turkeys on the same batch of oil before tossing it. It was getting a little murky, but tasted great.
They sell filters and such, but I find if you simply don't put stuff on your bird before frying (inject and season the bird immediately after frying) and don't get the oil too hot...you'll be fine.
I suspect you're asking..."who needs/wants to fry 10 turkeys?" Trust me. You start talking about frying turkeys and folks will come out of the wood work. Makes for a great Wednesday before Thanksgiving get together. Just get the word out and folks will be glad to chip in for oil (I think I ended up with about 20 beers and 3 or 4 half-full bottles of wine and whiskey, and a couple nice cigars not to mention the cash folks kept stuffing into my pockets...which almost made up for what I lost at the poker table that night).
Regarding fryers, I'm with BBQFANS. I now own at least 2 el-cheapo fryers and they work just fine. Get the basket so you can fry and boil other stuff (chickens, turkey breasts, chicken wings, fish, etc.) otherwise it's a uni-tasker that'll only get used for turkeys.
Kill your fire before you lower the turkey into the oil. Let it do it's thing for a minute or so and then re-fire it.