I am new here, thank you for reading.

I have an equipment builder sheet. In simple terms, column A is a description, column B is the price of that item & column c has a tick box. Currently, by selecting that tick box the cell in column B (the price) is then added as a value to all the other items that are also requested. In affect it adds all the columns B cells together that has a corresponding tick in column C and gives me a total at the bottom. This becomes the invoice amount for that piece of equipment. To add to this functionality, when i am selecting an option (using tick in column C) where this option demands other options to support its use I would like the sheet to automatically add a tick into the other required options. Is this possible and how is it achieved...? I would be so grateful for some help. Many thanks Matt