A four compartment sink will help you get through your work in a much faster way, which is why it is indeed a good idea to buy a four compartment sink instead of one with three compartments. However, you need to first analyze what sort of sink you really require. If you need to handle only a minor load per day, then you might be better off with a three compartment sink at first, and then move on to a four compartment one. But if your load is too heavy then you should indeed consider getting a four compartment one.
Getting a four compartment sink is not really a hard task; you just need to be able to choose a good sink from among different kinds of models. Then you will be able to get a high quality sink that you can use for a really long period of time. All you need to do is to find a good place to get the sink from, and you will soon be able to get the exact kind of performance that you deserve from your sink. So get a four compartment sink when you feel the need for it, and find a good one at that.