Excel formula

Hello,
I have a excel data file called BOQ. in which i have around 2000 line items in it. and many are repeating in many areas it is like a furniture supply BOQ, so same type of chair will be repeatedly comming in many location suppose. in 50 locations my chair Ch 2310 is repeatedly coming each time quantity will be different 9 like in room no 1 i have 20 nos of CH2310 and in room no 2 may have 40 and similarly many products.
now what i am doing is i am doing auto filter in the sheet to find out the subtotal of each items but if there is a change in the total quantity i again need to check the same which is not so easy in a big data file like mine.
so what i am looking for a formula whcih will search the model of the item from the column MODEL of my data sheet and give total quantity. in short i will have all the items below to my sheet in a small table format where i will write CH2310 so in quantity column i needs to get the subtotal of the items ( in this case 60 nos)
can any one help me to do so.