If it will be a problem when you downgrade your visa, only time and your bank can tell. But as a tourist you won't need all those things anymore, so no problem.
fact is simply you have to stay in the country you apply. When you want to break rules just find out yourself what can happen. According the grouprules of this group, advice for illegal actions should not be given here.
It is you that don't know the rules and then think others don't know what they are talking about. you should read the requirements yourself before you put misinformation here and are rude to others!
Non o based on being over 50 is definitely possible without having money on a Thai bank account, you can also use the option of monthly income.
Indeed a lot of people here obviously plan to abuse the visa once they got approved. That might also be the reason a lot of people do care if there are checks implemented at entry of the country. Legal applicants will have no problems with checks.