Different time slots for different product

This may be a dumb question, but can I setup different timeslots for different services/products? For example, a dentist may require only 30 minutes for each of her appointment while a mechanic will require an hour time slots for his services?

And at the same time, the mechanic may have a remote control car that he want to allow others to borrow it on a daily basis?

In summary, can one user setup multiple offerings using different length of time? And to further extend the question, can multiple users setup multiple offerings with different length of time within the same site? If not, any suggestions - multisite?

Thank you.