Order them yourselves
If you have gotten to the point where you have to order for a part, then another way you can save money is by ordering them yourself. In most cases, when you send repairers to buy parts, they could inflate the cost to maximize their profit from the task. Even when the cost is not inflated, you might need to mobilize them by paying their transport to buy the part. Buying spare parts online is also mostly cheaper compared to when you buy them offline. One of the places you can order from is eEuroparts. You should read eEuroparts reviews before ordering from their online store.