one thing I'd recommend you do is to start now, watching Craigslist and your local paper want ads for used canoes.

If you see a really good deal on something that meets your needs, jump on it.  you can always post a question here like - I see a xyz solo for sale - will that work for me?  or how much is it worth ?   

generally, really good buys go fast, though this is still the "Off Season"

and something to keep in mind - these boats are relatively cheap when compared to buying  a house or a car - if you get one that you don't like, just resell, likely for a small loss, but perhaps even for more than you paid - its not as complicated as getting a divorce!

I'd recommend buying an ultralight solo boat and learning to paddle it with a single blade, but whatever works for you.  Just keep in mind that ultralight boats don't want to be abused - you need to wet foot the landings and be somewhat careful with them - they aren't fragile, but they aren't super tough either.  if you are used to letting your fishing kayak grind up on shore to get out or shove off, you won't be doing that with an ultralight boat.