Living costs in Cambridge are pretty cheap, once rent is taken care of. You can find an approximate guide to living costs on the Undergraduate Study website – some students can exist on much less than this guide, and others would find that not enough – it really does depend on your lifestyle.
There are no transport costs (after the initial purchase of a bike if you choose, and perhaps the odd taxi home after a night out), food in the College Buttery is heavily subsidised, and student-run social and sports activities are generally low-cost.
Students who have additional mobility needs, either temporary or ongoing, can apply for a grant towards appropriate costs (e.g. taxis to lectures with a broken leg).
Newnham offers bursaries and grants towards a range of expenses, including book grants, research expenses, optional language classes and equipment costs, as well as non-academic activities such as sport, music and travel.