Dynamic HELP!? Selectable options

Hi!

Attempting to: Allow visitors to select “optional” parts with their purchase on my site. Each item would be linked to a price, so if clicked, the price would automatically increase.

I used an excel sheet (with checkboxes, but windows live doesn’t allow them) to figure prices out on my end BUT now that I’ve made a website, I’m not sure how the end user would get this? Here is what I’m talking about: https://www.recordyouradventures.com/rent/

Notice how it adds it up depending if you want it or not? How the heck do you make this look nicer than what I have??

Thank you in advance!