I am looking for some guidance on how possible it would be to write a script (maybe using js) that could capture specific data on a website?

For example if I wanted to capture the price and short description of a house for sale on a realestate website(like this one), is this possible?

I am not looking to aggregate this website information, more along the lines of a script that could once the page has rendered, capture key information I was interested in such as price and address and store it in a small DB.