I have my car serviced every 15,000 Km as per the maintenance guide. I always take it to the same place so I have a good relationship with them. It is the same dealership where I bought my car back in 2010.
I calculate how much I would need to spend every maintenance and budget it. This way, car maintenance is a regular budget item rather than a cause for surprise. I had budgeted 800 TL for my 105,000 Km maintenance but it came to only 627 TL even though they had to change the battery, some belts and a lamp outside the regular oil and filter change and other regular things. They cleaned the engine thoroughly and it looks brand new.
Car ownership is expensive especially in my country. We have the world's highest gas prices. No kidding!
I see some companies have recently begun offering hourly car rentals like the Zip Car. One day, I should sit down to calculate whether it would make sense to get rid of the car and just use a service like that. However, I think I intend to keep my car until it is no longer viable.