Event admission pricing help

I’m running an event and I need some advice on how to charge for things for attendees and for vendors. I’m having a day of presenters followed by a nighttime party with performances.
For vendors, here’s the info I have.
First year-event, so we can’t predict the attendance, and we don’t have a following.
One day event.
Multiple internationally well known speakers and performers
Multiple locally beloved speakers and performers
All the above will be promoting me with their following and at their other events.
Several local and regional promoters will be cross-promoting me at their events and via their email lists, plus of course my own efforts in the clubs I belong to.
Two part event means that there’s a different crowd for each, so access to more people.
Theme is Steampunk/Victoriana, which is super popular right now, and I’m near Hartford, CT, which is a hub for Victorian stuff, so lots of general interest out there.
People who already like Steampunk tend to have money to spend. They also tend to be willing to drive a few hours to get to an event.

All that said, how do I figure out what to charge vendors? An event a few hours away that’s only the evening and not the huge draw of my daytime charges $80, so I was thinking $120 for mine. I was told that’s high for a first time event. I was hoping to have the vendors cover the costs of the presenters. Is that unreasonable? I just came back from an event this evening that charged $800 for a booth, and it was full, but then I also do Ren Faires and SF conventions, which run $100 for the weekend or less. How do I work this out fairly? Also, how do I judge how many vendors to have? I’m only having one of any product, but I want to make sure they all do well.

For ticket price, the museum normally charges $6 for nothing but looking around. Another Steampunk event with just a couple of classes by one (admittedly awesome) guy charges $25 for the weekend. The evening-only one I mention above charges $25 for four bands and a drink ticket. A comparable event with a similarly stellar lineup charges $75 for the weekend or $35 for just Saturday. I was thinking $20 each for day and evening, or $35 together? How do I know if that will cover me?
Thanks in advance. This is more complex than I had thought!