You could be an independent laborer, or you could maybe work in something like a co-op where workers have a direct fair share of profits, but the business structure in which your boss completely owns the fruits of your labor because he owned the machines and paid you a wage related more to ease of replacing you than the value you produce would not be allowed, so there would be nobody to sell your labor to in the conventional sense, but you could collaborate and contribute your labor to something you actually got an equitable share of profits from. Communists would point out that you've sold your labor for less than it's worth in every single job you've ever held because that is the inherent nature of wage labor under capitalism. Your boss will only ever hire you if he thinks you will produce more value than the wage you agree to because that's the only way he can generate profits for himself. Anything else would make them no money or cost them money and therefore be bad business. 

 Would you invest your time in something, in other words sell your labor, for just your basic needs to be covered from it? Don't you want something extra for your time?

Isn't it my decision if I've sold my labor for what I think it is worth?

So all of this is just a way to keep people from making a profit? 

 Sure, I'd want more, but there's nothing central to communism that'd prevent me from getting it. A reason, successful implementation of communism would need to see your needs met AND enough surplus to pursue reasonable interests and goals in exchange for your contributions. You should be free to sell your labor, but communists view the capitalist system as inherently coercive because you're forced to sell your labor under threat of homelessness and starvation. I'd guess they'd want to provide basic needs so you were free to negotiate fairly and uncoerced to earn the surplus needed for those interests and goals. 

 So, how does a system provide for the basic needs of everybody? Who produces these basic needs? And then, if your basic needs are met such that you don't have to do anything for them, what do you do to get your extra? Produce someone else's basic needs and get a profit from that? So who pays that profit if not the guy who's basic needs are met?

Do you see how this concept doesn't hold water? 

 I don't think this seems that complicated. Imagine the same amount of work gets done, but we direct efforts towards ensuring basic needs are met first. Hell, say we lose a quarter of the work to inefficiencies and time off for workers. Stop producing most absurdly high end luxury items that 99.9% of society can't enjoy, cut back on producing frivolous shit nobody needs, and accept that having your every conceivable whim catered to for a price may not be feasible, but you'll live in quality conditions. I'm not saying it's the right call, but it's not that complicated. That's not the hard part. The hard part is running an administration for an entire country's economy and keeping the corruption out at that scale. It creates centralized points of failure, which are highly attractive to corrupt individuals.