Should I make a appointment to change tires

That would be best.

Anytime you can its best to make an appointment. If not there is risk of not being able able to rent a lift if needed.

If you're planning on a weekend visit, its a must to make an appointment.

You should always attempt to make an appointment just in case there are no available bays, especially if you want to pay to have the tires put on rather than doing it yourself, or need training on the equipment (Ron gets pretty busy helping everyone out.)

Yes

For sure, just call or pop in.

Yes you should