Is chanting better than donating money to Krishna?
Both donating to spread Krishna consciousness and chanting Krishna's names are good Krishna conscious activities. It depends on your own nature which one is better for you. It may not have to be an "either/or" situation. It's better to be an honest sweeper of the street than a charlatan meditator.
Most people can't fully engage in pure spiritual activities of hearing, chanting, and remembering Krishna all day. For them, it's better to be married and perform some honest work to maintain their families. You have to understand what you can do. You could try living in an ashrama for some time and see if that kind of life is for you.
Unfortunately, a certain amount of cheating sometimes goes on in business. This is unavoidable. If you change your business, you also may encounter the same thing. Arjuna was reluctant to fight on ethical grounds, but Krishna encouraged him to do his duty while constantly meditating on Him.
Srila Prabhupada said that a businessman should not give up his occupation because occasionally he has to lie. He mentions that a businessman says, "For you I make no profit." But without making a profit, how can he survive? Best is if you can keep dishonesty to a minimum, while maximizing your chanting, and making donations as you're able.