What flight documents are required when applying for a multi-entry visa to Thailand from the UK?

When applying for a multi-entry visa to Thailand from the UK, you need to provide flight documents that show multiple entries into Thailand. Specifically, it's often suggested to include proof of your flight in and at least one flight out that falls within the 60 days of your initial entry. However, some responses indicate that you may need to provide evidence for all intended flights in and out throughout the entire six-month duration of the visa application, which could potentially amount to four flights minimum. Additionally, there might be a requirement to show a bank balance of 5,000.