Sounds like you have all the usual issues of a busy father with a living to earn and family to keep happy: cost, do-it-yourself, do-it right vs. a deadline and get it done fast. These issues are manageable if you have some options and a production plan. Parts of the job you might want to sub-contract out if they make things go faster.
I would say the whole job looks like this:
First remove the old varnish and replace any split planks. If ribs are a problem, then things slow down a lot. Some use professional strippers (NOT that kind), if they can find one. Some go DIY with the usual home-use chemical strippers. After, wash real well and apply thinned boiled linseed oil to get the wood moistened up a bit. Some varnish at this point, before recanvassing, but that slows things down I think as you can varnish while the filler cures too.
Recanvas, DIY or have someone do it for you. Recanvas takes a day or less, filling 2-4 days. Then the filler must cure 3-4 weeks. Bill Clements (P.O. Box 87 N. Billerica, Ma 01862 978-663-3103) can do this for you. Also down your way Canoe Passage Outfitters in Raynham (Ray Brierly runs the whole show: 401-245-9025) has a canoe restoration shop that may be able to do the canvassing and filling for you. The Norumbega fellas can help you do the recanvas but the filling, you’d have to give some time to on your own. I’d say $3-400 to have someone canvas and fill for you.
So, then, once the canvas is on and the filler curing, you can clean up the outwales, thwarts, and seats, if they need it.
After the filler has cured (scratching with your fingernail should leave no mark), you can varnish the interior and paint (or paint and shellac) the exterior. 3-4 coats of varnish means doing it over 3-4 days as varnish must dry between coats. Ditto paint. Varnishing itself may only take 1-2 hours, depending upon how fussy you are about sanding between coats. Some varnish boats like they were a Stradivarius. Ditto painting. Some aim for an auto quality paint job and some are not so fussy.
Once exterior hull paint is done, reinstall outwales and stembands. Stembands can be tricky.
So your summer deadline is certainly not impossible: depending upon how much you choose to do yourself and how much spare time you give it. The first time I did a canoe it took me nine months as I had no WCHA network to help. The second time things went a lot faster.
Pfds are personal flotation devices, Life jackets.
Floor rot is the big problem in my 86 and I can’t find anybody to tackle it. The one body shop I took it to said buy a new Volvo and I said they don’t make 240s: I keep the car for its capacity and canoe carrying. I got it at Dalzell in Dedham when the old man still had the place (86) and before they became Ford-Vo. My mechanic—a great guy-- keeps shaking his head at me over the floor rot. Mine has 171k on it, but otherwise very sound. Rocker panels are in poor shape but I can live with that. I’d consider a low mileage later year 240 wagon, if I could find one, but people who own them, like me, are loathe to part with them.
I'd be glad to try to come down your way this weekend and eyeball the job for you.