Party question-come on u know you want to answer this question lol. por favor?!

I'm having a sweet 16 party, that from the looks of it may be amazing!. But there are often times where even big expensive parties end up being lame!.!.!.so I need you guys help!. So It's going to be outdoors in my backyard!. We have a brick ground for dancing, a deck which is sort of like a stage, a pool and hottub!. I want it to just be a dsance party, but we were thinking off having a guitar hero staion in one area!. I want it to be dark so the only real like you get it from the smoke machine and party search lights!. The only problem is, our neighbors house is pretty close to ours!. I don't want to blast music while they're trying to sleep ( some of them are elderly)!. What time of night should I have the party so that it's still dark but doesn't go on all night!? also how many people should I invite to make sure everyone keeps dancing!? ANYY tips are welcome!. Thanks a lot :)Www@Enter-QA@Com

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