How long it takes to build a boat, depends greatly on what kind & size boat you want to build - and how closely you follow directions, as well as how good you want to build it.
Here is a link to hundreds of boat building plans - pick one, and read all the information on it.
It will tell you "about" how long it will take.
http://www.glen-l.com/
I built boats for almost 40 years. Some small 'fishing type' boats take little more then a couple of weekends, some take a couple of weeks, some months, and my last one took a little more then 7 years. . . They have some small 'dinghy' and 'jon' boats that can be built in a weekend.
More then likely, from the sound of things, for what you want to build, if you have the money, the tools, and the materials in place, you are probably talking a weekend to a week to build a simple "jon boat" or similiar type small fishing type boat. A "Bass Ranger" type boat will take two or three weeks - maybe a month - assuming of course, you have the time to devote to it.
I've done business with Glen-L for 40 years, and they have great plans on great boats of all types & sizes. They are also great people to do business with. They have excellant easy to understand plans with great instructions, and will provide you with help and support, and answer your questions until you finish your boat building project. WIth their plans & help - it is easy to build a great boat you will be proud of.
PS. It's much easier then you think - even with fiberglass over plywood.
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