I used to live in Vegas, but I grew up in upstate New York. While I can’t guess on costs for a Niagara elopement, it would be a beautiful wedding… but I’m definitely thinking it’d be more expensive than Vegas (though cheaper air, so it might work out). However, flights to Vegas can be fairly inexpensive.
You can get a chapel for under $100 all the way up to a few thousand for the nicer Strip casinos, but that usually doesn’t include the officiant tip/fee/whatever. I eloped to Reno, and my chapel fees were around $80, but with tip/officiant fees AND marriage license ($60 in Nevada, I believe) it came in just over $200.
You can find rooms in the Strip casinos from $30 on up, just depending on what you’re looking for. Rooms bump up in price on the weekends, and the casinos toward the center (Paris, New York New York, Bellagio) tend to be a bit more expensive. I stayed 2 nights in the Stratosphere once (the huge Seattle Space Needle-like casino), for $35/night before taxes, plus I got free passes to go to the top of the needle, which is normally around $20 a person (I think… that a couple years ago). My parents regularly stay in The Quad (the former Imperial Palace). It’s in the middle of the Strip, but they get free nights from gambling.
Another point: if you can, sign up online for the player’s club card for the casino you want to stay at. You’ll usually get cheaper rooms, just for signing up. I don’t know if you’re near any casinos, but if you’re near an affiliated casino (for instance, Harrah’s, Flamingo, Bally’s, Rio… all affiliated) go and sign up for a card. You’ll get mail from them – if you’re lucky or if you gamble even a little, free hotel nights, but at the very least they usually send food coupons, give-away information, that sort of thing. Also, when you gamble with the cards (I don’t know if you’re into gambling or not) they send you MORE free stuff, plus you get points, which you can usually put toward food at the casinos. Thanks to my parents player’s card, we got our hotels in Reno for $70 (for the weekend), and a buffet for 10 people for $45. It’s usually $23 a person.
Sorry for writing a novel!