I need some custom code modification. Can you help me?

1. I need to add category on "groups"'s plugin.
2. When an user choose a category, he must reply to some questions that administrator set (section about of facebook)

example

Category "band" obbligatory questions:

Band name:

Facebook link:

Category "computer" obbligatory questions:

Number of progessor:

Gb of Ram:

The questions are set by administrator when he crate a category.

3. User can create an event (i have "eventx plugin) from the group page and the event will show to the page group.

Who can help me and how much it cost?

Thank you