I have always billed for any items which I have issued a purchase order for such as lighting packages, gear, generator, etc. and do not wait until I am billed for it. I also keep the schedule of values simple and do not break out general labor and material. A generic job would have the following break out.
Engineering Permits and fees Mobilization Temp Power and Lighting Underground/Site work Service and Feeders Branch Circuits Lighting Low Voltage Mechanical Rental Equipment General Conditions
American Institute of Architects It is a set of standardized documents and contracts. The documents are a set of forms required to be filled out and sent along with any/all invoices. Usually required on large projects which are being funded by a bank or other outside organization. ( a google search will tell you more than you may want to know!)
[This message has been edited by kentvw (edited 11-14-2004).]