When you own a vehicle, it is a good idea to document all that you've done to it, and also keep a record of fuel usage, modifications, and all other significant work. This helps you maintain your vehicle at the correct intervals, and adds value to the vehicle if you ever want to sell it. A "dollar store" notebook kept in the glove box and a handy pen is all you need. Having oil changes done by a shop such as Pep Boys is just a bit more expensive than doing it yourself (especially if you don't have a shop or garage to work in), establishes a
third-party record which can be used to establish that you cared for the vehicle properly if you want to sell it later. Most importantly, putting a vehicle on a lift periodically for inspection can catch problems before they become serious enough to become expensive or safety issues.