the Piano Lesson #2

I wonder why Lymon is helping Boy Willy sell the watermelons? It explains why Boy Willy wants the money, but never why Lymon does. and I don't understand where Boy Willy got the idea that Maretha was just going to give up playing the piano and just start playing the guitar, so it kind of annoys me that he just assumes she wont mind and how he doesn't even think about how she will feel when they discuss this with Doaker. My first impression of Doaker was that he didn't really bother with other people, and I thought that he seemed almost rude, but now reading more about him i think that he is actually more of the quite watchful type that has a really good opinion about things. I feel like he is a person you can ask for advice if you need to.