Bob S,
First, I have to warn you, buying WWII weapons will be addictive. It is not, however, particularly hazardous - except to your savings account.
Second, you picked some good ones to choose from. Eventually, you will want a good shooter (because you really do want to know what it's like to fire these rifles, after all) of all three, and you should probably throw in a Carcano and a Mosin Nagant, just to keep things on an even keel. Then there's the different variations of each, the other service rifles, the handguns, SMG's, etc., etc.
See, I told you it was addictive!
Personally, I would start with the Enfield, either a #4Mk1 or #4Mk1* (Canadian made). Then, I would get the Mauser. Then, save up, get the Garand (you should look into the CMP for that) ASAP. I wouldn't argue with anyone who picked a different order - it's mostly personal taste & interest. All three are pretty doggone rugged weapons, that if well cared for, you can pass on to the next generation.
I have purchased some of those "$65-100" Enfields - some are in good shape, some are not so good. That's surplus rifles for you. As far as actually purchasing your rifle, I would recommend spending a few extra dollars and try to find it at a local gun store or gun show, or maybe even a pawn shop. That way, you can actually see what you're getting. I've just heard a few horror stories from people who ordered surplus rifles (and a few "I got better than I expected" stories, too). Getting a rifle you know you'll be happy with is worth a little extra time & money.
Enjoy!
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Beginner barbarians probably had the idea that every house they broke into would be full of untouched loot and frightened, unarmed victims. It just doesn't work that way, my friend.
I hope these evil men come to understand our peaceful ways soon - My trigger finger is blistering!