thats rather steep that is book price for 5 litres of longlife oil in retail packaging. (so not from the large drums they will use in service) you should ask them the cost of a minor longlife service is or see if they will let you supply your own oil.
Or do it yourself, you will be able to do the whole lot, oil oil filter, and air filter with sump plug for £70 plus some satisfaction and thats with OEM parts from the dealer.
