Is it enough to take 3000 Hong Kong dollars to travel to Hong Kong?

If you don't stay, you can go and come back the same day. See how you spend it.

Besides transportation and meals, there are more than 2,000 yuan for shopping, depending on what you buy. In Hong Kong, you spend money in Hong Kong dollars. If you bring Hong Kong dollars, you need them everywhere and you don't need to exchange them at all.