To what extent could old ballgowns be modified for new fasions?

It was relatively easy, and a common practice to recycle clothes, hand them down, sell them or give them away. I think it's perfectly reasonable that the Bennet girls would hand down dresses to each other,and also make over the ones they have. In fact, in P&P2, Lizzy's white ball gown does get a make-over between Netherfield and Pemberley.