I am still reading Bruce Longenecker's new book Remember the Poor: Paul, Poverty and the Greco-Roman World (Grant Rapids: Eerdmans), 2010. But here is what I found from a quick look at the final pages.
We have seen that Paul's concern for the poor had considerable impact on the way that he lived his life, to the point of risking his own life in "putting his money where his mouth was." This should surprise us only if, unlike Paul, we imagine the "good news" that transformed Paul from persecutor to apostle to be devoid of an economic dimension. But since Paul envisioned an economic component to lie deeply embedded within the good news of the Jesus-movement, the fact that his concern for the poor influenced his manner of living and his approach to peril falls wholly in line with all that we know of this man who, when committing himself to a cause, did so wholeheartedly, and with spirited enthusiasm. (page 316)
I have long been thinking that it is hard to read the stories of Jesus and Paul's letters (and Paul's life story in Acts) without being challenged to live a self-giving life as Christ's followers. And this self-giving life can hardly not include some kind of sacrifice in terms of lowering one's socioeconomic status. I think Longenecker's detailed analysis affirms this rather obvious observation.
(So far - I'm reading chapter 4 - I find Longenecker's analysis of the economic situation of Pauline churches very thorough. He interests with the most recent and the earlier scholarship really well, and has come up with a balanced view on the matter.)