Data Table for Scenario in Excel

Trying to make a scenario manager in excel for cars and engine and body costs.

1. select car model in A3.
2. have a table of results based on base case cost for all models. (linked by data validation to sheet 2).
3. be able to change the engine and body cost in cells C3 and C5 in sheet 1, and see what effect that would have on the cost of all the car models assuming the same % increase/ decrease was applied.
4. plot results on graph on same worksheet.

Example attached.