Sum if a number is contained in a list

[pauldaddyadams]

Hi,
I need some help with either a sumif or sumproduct formula if possible...

I have uploaded an example file and I need a formula to sum only the entries that are listed on the lookup sheet which match the contract name.

In order to do this the formula will need to look in column G and if there is a match on the lookup sheet then sum column Q. It would also need to match the contract name column U with Column B

I have provided an example of what I need as my description is not very clear.

The formulas would be required in the pink cells.