Construction Upgrade Pricing Spreadsheet

I need a single, well-structured spreadsheet that lets me catalogue our construction options as product listings and instantly see how any upgrade affects the price. For every option I must be able to store the base description, the base price, and one or more upgrade costs. Toggling an upgrade (via checkbox, dropdown, or similar) should recalculate the option’s price and roll the difference into a running project total so I can show clients the impact in real time.

Please build this in Excel or Google Sheets—whichever you’re most comfortable with—using clear formulas and clean formatting. The file should arrive fully unlocked, with an instruction tab, and ready for me to add or delete options without breaking the calculations. A quick test set of sample data is appreciated so I can verify everything works before I swap in our real figures.