I assume you are doing Pro/Am, otherwise your instructor wouldn't be charging for any of this.

It is customary practice for Pro/Am students to pay for the following when competing:
* your entry fees -- Try going to http://www.accessdance.com/dance_competitions/
to see if the competition you are doing has a web site. If so, you can often get information about entry fees and ticket prices from the site.
* your admission tickets to the ballroom
* share of her own travel expenses, including hotel, airfare, meals, parking, etc. Note that the travel expenses should be split between all the students who she brings to the competition to dance with her.
* share of her entry tickets to the ballroom for the sessions she will be dancing with students, again split fairly amongst the students either by who is dancing how many entries in which session, or just an even split overall
* Some teachers also charge a per-day fee to cover "lost wages" that they would have made if they were back in the studio teaching. Not all teachers do this. The lost wages should also be split fairly between the students.

Pro/Am can get very expensive. I usually spent about $500-$800 for a local competition, and about $1200-$2000 for an out-of-town one.

I do not know of any teachers who charge students for costuming and makeup.

As far as her also going to compete with per Pro partner, that usually has little or no effect on the price.