Make sure you aren't going on a Canadian holiday. Understand that A LOT of people want to see the Falls, and that A LOT of people are going to be there at that time of year given school is out. IMO the dinner buffet in the tower is 100% completely NOT worth the time, money, or the effort. Honestly speaking the best meal I had all weekend was outside of Buffalo out in the boondocks at some place my wife found online on our way over on Friday.
Call me a fuddy dud...but what I saw of the Falls in about 20 minutes was enough for me. The rest of the time was just expensive air breathing. You stand in line for everything, just like Disney. I've been to Disney many times, and I'll go back. I'll never go back to Niagara Falls. Sure..take the Maid of the Mist boat ride, that is fun. The other stuff? Journey Behind the Falls, etc. etc....a huge money grab.
Lots and lots of walking involved....and that hill is no joke. We stayed at the Holiday Inn on the CA side and it had breakfast. It was...ok. $195/night ok? No.
If you take the Rainbow Bridge across on a Friday night, be prepared to sit there for a couple hours. Coming back on Sunday morning into the USA was a breeze.
You'll have a grand wrapped up in that trip in no time. We weren't there for more than about 36 hours and we spent more than that for 5 people. Every meal we ate was $100 minimum.
You learn all you need to learn when you see the junk souvenir shops all over the place. That is the element that is in place there.