ITEM INVOICE CALCULATION WITH MONTHS

ITEM INVOICE CALCULATION WITH MONTHS

Dear Sir,

My Invoicing item working has Item Qty * Rate * Months, As Rental System

Example I am doing Rental business of Computers where per Computer Rent is 2000 per month.

So If my Customer has requested 3 Computers for 3 Month then Invoice Will be

Item----------------- Qty--------Month-------Rate--------Value
Computer - -----  3 ------------ 3 ----------- 2000 ------- 18000 (Qty * Month * Rate)


1. How get above result ?

2. Can we change Title of Qty to Numbers or any other ?

Pls suggest for the above Two requirements