No 500,000 sitting as savings in the bank then you will get rejected, need to meet the criteria regardless your income you need the money in the bank and also will be checked each 180 days
If you stay 180 days or more in Thailand within a 12 months calendar you are classed as a tax resident probably why immigration tells you get the correct visa as you are not a tourist and can refuse your entry due to the length of stays,
this is what immigration states when questioned at airport, January my friend was told the same when entering to many times and more than 6 months, other friend got returned back to Cambodia due to staying 9 months without correct visa, both now have DTV
Dont just copy from Google as this information isn't correct, their is a limit, you can only stay 180 days as tourists in a calendar year that's January - December and if found to be staying longer you can be refused entry and sent back, money on hand doesn't do anything unless you think your gonna bribe the immigration officer if caught attempting this with the wrong person you can also get banned, always get the correct visa for Thailand or stick within the laws, land border bounces or unlimited flights but maximum stay 180 days or get ready to be questioned and possibly refused entry
Policy says no refunds so a charge back will result in a loss to yourself and also an bank admin fee usually around $30, if you got rejected just face it don't be a #### try again or another embassy
Show the funds long term in the bank in your western account better than just transfer a few days before into Thai, their looking to see you have long-term funds not just recently deposited