Proverbs 31:16: (NKJV) "She considers a field and buys it; From her profits she plants a vineyard."
An overreaching quality of the virtuous woman that is described in various ways throughout Proverbs 31:10-31 is the quality of being a hard worker. Proverbs 31:16 describes yet another way that the virtuous woman is a hard worker: she is a hard worker in her financial dealings. It takes a lot of effort to do the research necessary to make a purchase that will be profitable! The virtuous woman isn't simply satisfied with her earnings either - she puts her earnings to work for her future.
However, in addition to being a hard worker, another overreaching quality of the virtuous woman is also described in this verse: wisdom. She doesn't spend her money carelessly. She takes the time necessary to do her research - and her research pays off because her investment is profitable. But his wisdom doesn't end with her profits: she continues to invest wisely by using her profits to continue to provide for her family.
I'll freely admit that I have not (and still do not) always put forth the proper effort, work, and wisdom when handling financial matters. As I've gotten older, and wiser I suppose, I'm trying to make better financial decisions by exhibiting patience and self-control, as well as through good research in financial handlings.