What are the costs and requirements for extending a Non-O visa in Thailand?

When applying for a one-year extension on a Non-O visa in Thailand, you can expect to pay a fee of 1,900 baht directly at the immigration office. If you need a re-entry permit, it costs 1,000 baht for a single entry and 3,800 baht for multiple entries. It's advisable to make an online appointment to avoid long waiting times. Note that while initially obtaining a Non-O visa might require proof of funds (800,000 baht in a Thai bank account), this may not be necessary for extensions. Always have the appropriate documentation ready to ensure a smooth process.