Oil change is the first step

for DIYer. If you can't do oil change, whatelse you can do?
In the money sense, I have three cars, I do oil change three times per year, over years I do save some hard-earned money on oil change alone, don't mention lots of other maitainance.
Besides, I don't trust those guys in quick oil change store. I have heard many, many complaint against them, very bad. For my own cars, I use OEM filter ( ordered online), good quality oil and very careful operation.