I have a 2015 Mitsubishi Outlander PHEV, owned since almost new and has done 38,000 miles. Each year I have had it serviced at a local dealer. This year, I've only done 2500 miles since the last service - only approx. 600 miles of which has been using petrol power. It's now due for an annual service and all tasks due appear to be age-related. While I appreciate brake fluid must be changed, do I really need to change engine oil and filter? Historically much work I believe was mileage related. Any advice on essential maintenance for such low usage would be appreciated. The £450 I have been quoted for the service seems high in the circumstances. Best regards.