I m a sky engineer. a free view card from sky is around 20 quid, you do get freeview channels but not all of them .
The main channels 1-5 all have hd equivalents and they are all free to view.
My advice would be get a freesat box because if its a recordable sky box you have the recordable part is part of the subscription. I got my grandmother in law a freeview card for one of my old sky boxes and had to ask our cust service very nicely to add sky plus to the card but I only got it because I m staff.