You’re right practice can vary between embassies and ever between personnel handling the application, but generally no onward ticket is required for long stay visas.
Our embassy in Norway doesn’t require onward ticket for a Non O visa. They even issues tourist visa just with an inbound ticket. Onward ticket it’s not required for Non Immigrant visas.
Required Documents:
1. Passport or travel document with validity not less than 6 months.
2. Photograph of the applicant, taken within the past six months.
3. Financial evidence in English: applicant’s bank statement showing a balance in the amount of not less than 800,000 Baht – or a pension certificate with a monthly salary, after-tax, of not less than 65,000 Baht/ 20,000 NOK, for example from NAV or insurance company (NOT selvangivelse or skatteoppgjør) –
or a combination of a deposit account plus a monthly pension totaling not less than 800,000 Baht a year.
4. Proof of accommodation: Copy of hotel reservation / rental contract/deed. In case of residing with a family, an invitation letter from the host family along with a copy of their undersigned Thai ID or house registration is required. The name of the applicant must be indicated clearly.
5. Copy of residence card or other evidence to prove that the applicant is legally residing in Norway (only for non-Norwegian and passport holders)
You can do two border runs in a calendar year by road, and you haven’t done any this year (unless you entered by road in June) and your previous stay is not too excessive. You will be fine with a border run and they wouldn’t bring you if they weren’t confident about your being ok. There’s no six months rule.
If you’re in Bangkok I know several people are satisfied with their service
That’s also my experience in Buriram, but I needed to do both tests from scratch with theoretical and practical test since I don’t have a motorcycle license from home and didn’t bring IDP for car.
You’ll just have to justify your need of a multiple entries instead of a single entry tourist visa. The best way it’s by two inbound and two outbound tickets, but not all embassies/consulates are equally strict regarding this. You could call the one who serves you and ask to be sure.
Ok, you can’t do another border run by road to get a third visa exemption now, but you can leave by road/air and enter on a third visa exemption by air OR do a visa run to the embassy in Vientiane or the consulate in Savannakhet, get a tourist visa and enter by road OR air.
Be aware of that both require online appointment now and I know people have been struggling with getting a suitable appointment.
3 in a calendar year then. That’s excessive and formally not allowed unless you have a visa. If you’re going to do one more I would have used a professional land border transport company. They don’t let you go unless they feel confident they will manage to get you another visa exemption. I don’t know if it’s possible, and I guess your best and most accurate option option is to do a visa run to get a tourist visa and try to re-enter by a land border. If you’ve stayed in Thailand on visa exemption and tourist visas since December you could potentially be questioned and told to get a proper visa next time.