Extracting data with different combinations

Hi All,
I'm trying to pull data from a spreadshett I've creted and now I'm stuck and not sure if it can be done.
I have uploaded a example sheet but essentailly Im trying to create a formula that will count a quantity of parts based on different conditions.
In the example I have 4 products (Coiulmn B-E) they are made from 19 parts (Row 2-20).
I have an original quantity in a bin that will increase as I add each proudct to it as can be seen in Coulmns H-I.
What Im after is a formaula that will calculate the quanity of parts for each new product to provide the totals in Coulumn I. The values I need to automate bearing in mind that some parts are not unique.
Additional to this I then need a formaul that will provide a total if i remove a Product as shown in H-I9.

So in short a formula that will provide the totals in 12-5 and a formula to provide the answer in I9 based on any proudct I decide to use.

Hopefully all that made sense, Im not sure if it can be done but I'll keep my fingers crossed.

Many thanks in advance.

https://www.excelforum.com/attachmen...1&d=1515587633

Hi Glenn,

I1...100 is a qunatity already exisiting.
I2 is the addition of 10 parts used on Product1 to the exsiting quantity of 100.
So the expected answer is 110, if I then add the unique parts from Product2 to Product1 as shown in I3 I get 113. (100 original quantity + 10 parts form Product1 + 3 parts from Product2)
Hope that helps?

I should also have said that its the number of parts rather than the actual quanity So Product1 is made from 26 items but only 10 individual parts. Its the individual parts Im counting not the overall quantity.

FlameRetired.....You Sir are a genius! Many thanks that worked perfectly saved me a whole heap of work.