Hi Scott,
You are probably talking about a month longer, at least for planning purposes. As said, fall could make this longer too. I'm assuming that this would be a very leisurely trip, otherwise you would not consider the extra distance.
As far as saving
money, you'd be better off on the canal. Nearly every town has a free wall (terminal wall or lock wall), many with free
power or
water. You could do the canal at a very relaxed pace staying put to sight see every day, and taking a month to do it.
Weather is largely not a concern here, other than occasional high
water that subsides after a day or two, and obviously storms.
The
mast needs to be dropped, but the
Hudson end has a
DIY pole for $55. Buffalo you have to pay the going rate. Also, the Welland (and other?) canal requires that you have 3 people on board. The Erie has no such requirement.