They use hot desks which you have to book in advance, which personally I'm not a fan of, I prefer to have a fixed desk. However you can block book a desk for a number of months in advance. This is just down to personal preference really.
You use the same laptop for working in the office as you do for working from home. If you want to work from home but you don't have your laptop with you then you have to go into the office. I'd prefer to have separate laptops for home and office working.