Is it cheaper to rent privately or live in uni halls?Watch this thread
That said, if you don’t plan to be in York over the summer, you’ll likely save 3-4 months rent staying in halls as most landlords will want a 1 year contract covering the summer holidays at a minimum.
Also for living outside of halls, rent is usually not (although sometimes will be!) inclusive of bills and utilities, and of course you will have to "self cater" while living outside of halls so will need to account for food costs. Also usually private rentals will be further away from the uni and/or in less desirable areas otherwise, so there may be additional commute costs (or non-financial QoL costs) involved. So again, the difference may be smaller than it seems off the bat (especially if one of you isn't a student and you have to pay council tax!).