Need a special event scheduler

We have a number of real estate sales reps who show properties. We would like to be able have an event scheduler that will allow the reps to schedule showings, which property they are at at any given time, along with a graphical timeline, eg Joe is at 123 Main Street from 2PM to 3PM, with a solid bar displaying that time frame. (Color coding would be great too for each rep).

This means that the scheduler must allow for a time slot to be occupied by more than one rep.

Also we need an admin to create accounts for the reps, with passwords and emails. Ie the user should not be able to do it.

I guess this may be asking for a lot, so we’d be open for proprietary solutions as well.