Reuse admin interface in frontend?

I was wondering what would be best practice, in terms of performance and code reuse, for the following:

I’ve got a plugin admin area almost all writen and usable in admin area, but i want to give some users change and editing options for database table data, that is also changeable from the admin area.
So, what would be the best practice: Reuse (how, if it’s possible to know…) the admin code that allows users to edit data WITHOUT entering the admin area (which they would never be allowed), or rewrite all the code again for those frontend editing area?

Has anyone tryed this before?

Thank you all…