Firstly, you do not have a visa of any description. You have a "visa exempt" stamp in your passport which is not a visa. It sounds like you have entered Thailand many times using this method and want to stay lonmg term in the country. The visa exempt entry is intended for tourists and not for long term stay. At some point soon Immigration will deny you entry into Thailand. You need to get a long term visa from outside of Thailand related to the reason for your stay in the country.
If you are in Thailand. you are applying for an extension of stay based on being over 50 and not a visa. And if so your money needs to be in a Thai bank.
Now the 60 days visa exempt stamp is automatic. They rarely ask for the 3 proofs unless you have abused the visa exempt system by entering too often. But the money proof is per adult.