If you want some help with ideas you should check out these cafes.
Look at their prices, food, games, maids, and how the building is set-up.
Then set a budget; I'd also recommend that doing something where, during a certain time (lunch, dinner, etc.) You have Cosplay time then you have maid time. Cosplay time is where the workers wear any cosplay or the cafe sets a theme. (Swim suit, Ninja, Teacher, Animal, etc.) and Maid time is where the workers wear the same Maid uniform.
Because if you stick with official uniform image it will help promote your cafe.
Here's a link to ALL of the cafes in Japan.
http://moeten.info/maidcafe/http://www.royal-t.org/ (This maid cafe is in Cali) since they’ve been here this long they must be doing something right. lol
Here are the rules for all Maid cafes;
http://www.youtube.com/watch?v=EqOW_87_gNk1. Do not touch a maid's body
2. No asking for a maid's phone number
3. No asking for a maid's email address
4. Don't infringe on a maid's privacy by asking what time she gets off work
5. Do not stalk or persistently pick up a maid
6. Don't linger outside the cafe waiting for her to come in or go out
7. No harming the employees, guests, or neighbors of this cafe
8. No taking photos of the maids or the interior and exterior of the cafe ( They charge $5 for a photo with a maid)
9. Don't bring outside food or drink into the cafe
10. No smoking on the stairs outside the cafe
Here are some Theme cafe videos;
http://www.youtube.com/watch?v=5S0xA4V2tgc&feature=fvwrelhttp://www.youtube.com/watch?v=F0TOW1xTGMg&feature=relatedhttp://www.youtube.com/watch?v=bqGv0kR_yMk&feature=relatedhttp://www.youtube.com/watch?v=YOucsztZJSwBut really it's a lot of work. I tried doing one myself, but it was going to cost around $20,000 just to start. So you’re going to need a huge team, lol. I think the best thing to do is ask a cafe, bakery, etc. and see if you can team up with them and do a Maid cafe event, just to get a feel of how your team will be and how much you can take. Because opening a place is a HUGE thing to do, and takes months even years to get ready. I really wish you luck ^_^ because I would love to see this happen, I would even drive there and work. Portland, OR needs a place like this and I think it will be a lot of fun.