Full service, as in new: spark plugs, air filter, oil filter, pollen filter, oil, coolant, diff oil, brake fluid change?
Your garage can do this for £160? Is that including parts, labour, VAT? Seems too cheap to me- unless they are using cheap/poor quality service items.
For example, a set of NGK/Denso irdium spark plugs off ebay cost about £45 and a K&N air filter off ebay is about £37. A Toyota oil filter (with draining nut washer) is about £10 from Lexus/Toyota.
I'd double check with your garage what their idea of a full service is.