It's very easy to do yourself. Use the official passport agency in soi 13 Bangkok (VFS). Everything is explained online. Download the forms, email them for an appointment, go submit your documents in person and pick it up about 10 weeks later when they tell you it's ready. The VFS people are very friendly polite and helpful.

Roojai car insurance can add breakdown cover to your policy as long as it's not over 12 years old (I think it's 12). They have a mobile app. So if you call for assistance, they know exactly where you are (even if you don't).there is also a nationwide breakdown company here but can't remember the name. (Green flag???). Finally the vehicle manufacturers handbook usually has a nationwide list of dealers at the back, you could call the nearest dealership.

When i hadn't cancelled my work permit a few years ago, the next time i applied for a work permit, i had to pay a fine because it was on the system that my previous wp had not been cancelled. If i recall correctly, it was a 100 baht fine. Like most things here, much depends on the particular office and the particular person you deal with.