For the remote worker category, you need a pretty decent income, but it's not that high.
The issue is that you need to be employed by a publicly listed company, or a company that has at least USD50 million revenue per year. That shuts out pretty much all small-medium business owners, or employees thereof.
for proof of business/employment, you generally need to compile all the 'evidence' into a single pdf. max file size is 3MB. That was slightly challenging...
Anonymous participant it seems that most 'western' embassies that are issuing e-visas have no requirement for months of balance or transaction history. The statement I submitted had only 2 days of transactions and it was fine (Australia).