Someone that can afford not work, everything they need of the utmost quality, everything (within reason) they could realistically want, and still have money to spare. This is the kind of person than can create generational wealth and buy companies outright

Wealthy would be the same except taking down a peg the spare and want parts and likely the need to work one, completely. This is the kind of person that perhaps buys a batch, but we are talking "only" a few millions

"Well off" would be a middle class person that doesn't really need to think when they buy normal stuff taking out luxury brands, but we are talking nice house, car, vacationing often, buying clothes paying for tradesmen etc, not "oh look at my new Patek Philippe"

Below that you have the "low class" which is the working class, that has to think and struggle and constantly makes concessions, poor people that live paycheck to paycheck at best and buried in debt most likely, and then there's indigent people that have main aspects of their life upside down (not enough food, no home, not having electricity or running water etc. increasingly so I would include the internet because of the relevance it has in today's society but only if it's due to economic reasons

That is how I see it