Renting cost = all rent paid over the period (with annual rent inflation). No equity built; deposit stays invested elsewhere.
Buying cost = mortgage interest + buying costs (solicitor, survey, etc.) + maintenance. Principal repayments are not a cost — they build equity. Stamp Duty is not included here (use the SDLT calculator) — add it to buying costs if needed.
Equity if buying = deposit + principal repaid + house price growth over the period. This is wealth you keep.
Opportunity cost of the deposit is shown separately: if you rented, that deposit could earn interest elsewhere.

Assumptions: fixed mortgage rate, no overpayments, no selling costs, no tax on gains. Real costs vary — get personalised advice before deciding.