You'll need to look for a specific bit of information (card price) in a large html, it can be challenging.
https://en.wikipedia.org/wiki/Web_scraping
I asked someone how they do it for their website and this is what they said to me
"I actually get the prices manually from the seller page and then process the CSV file. It does not require a key, but I think it might require being a seller with a certain number of sales."
I don't know if this can also apply to construct or not.