You’ll have to get the specific requirements from your immigration, but for tourists extension is normally only passport, copies of latest stamps and ID-page, a pass-photo, receipt of your TM.30 if asked for, 1900 baht in cash and you apply on a TM.7 form at the immigration.
Yes, but I think OP might mistakenly have applied for a 60 days tourist visa valid for 90 days at €40, instead of a 90 days Non O visa valid for 90 days at €80.
With Non O you don’t need to provide any air tickets either.
A 30 days extension is 1900 baht. 4000-5000 baht with an agent. Total waist of money. Easy peasy, passport with stamp, pass photo, receipt of TM.30 if asked for, 1900 baht cash and apply on a TM.7 form at the immigration.
60 days visa exemption is free. A 60 days tourist visa is still € 40 at the Thai embassy in Brussels. A 90 days Non Immigrant visa is € 80 in Brussels.
You might have applied for a 60 days tourist visa valid for 90 days.
You don’t need to upload any flight tickets for applying for a 90 days Non O at the Thai embassy in Belgium. And the fee is € 80. Single entry tourist visa cost € 40 as you paid.
Are u sure you didn’t apply for a 60 days tourist visa valid for 90 days. Non Immigrant visa normally cost the double of what you paid (€80) and there’s no onward ticket requirement, in fact you can apply without uploading any tickets at all? Tourist visa can be more strict regarding this.