My local vinyl floor store gave me their sample floorings for free that they didn’t need anymore and they were sorta small but I layered them and put matts over that for added security
But since my rabbits are chewers they managed to make holes by digging away the matts and chewing the edges
So then I went to home hardware and just bought a roll out vinyl flooring, I guess they are officaly called vinyl sheets
https://www.homedepot.ca/en/home/ideas-how-to/buying-guides/flooring/vinyl-flooring.html
There’s a picture of one on this website, I got the sheet kind like I said
Mine only was 100 bucks which wasn’t bad overall and you just roll it out onto the ground and there you go!
I’ve since gotten rid of it because my rabbits are fully litter trained now and they haven’t big digging the carpet anymore so I didn’t need the protection for my floor but it worked very well in protecting my carpet