You can easily disguise prostitution as consensual non-commercial sex.

I would tend to agree with you on that.

When people discover an avenue to make money they will take advantage of it immediately.

I wouldn't say immediately. But I do know (first hand) that such things do occur.

Arguing Devil's Advocate here... Making this legal takes away a major hurdle for people wanting to cash in child exploitation.

Should this be legalized, wouldn't there be a lot of regulation to it all? Wouldn't things be a bit more civilized? A bit more safe for the child?