How much postage for the following shipment?

Hello everyone,

A few months ago, I bought three window films, each 45 cm long and 5 cm wide. I'm undecided and don't want them anymore.

I'd like to sell these three narrow rolls on eBay. Can anyone advise me on how much postage I should charge for this? And, more importantly, how I could ship it?
Unfortunately, I have no idea about shipping. I know how to send letters and what the postage costs are.

But with something like this… 🤷🏻‍♀️