How to Allocate equipment use in a project

SUGGESTED

I have just started to use projects.  Allocating payroll, and various expenses are straightforward, but not sure how to go about allocating the use of equipment.  Scenerio: I have allocated the total of the drilling service to a project on an invoice.  However, the cost of using the backhoe for the job needs to be accounted for.  Do I set up each piece of equipment as inventory items? or?