The cost of any build is directly related with two things, displacement and level of finish. Vacationer being the biggest, will require the most materials, build time and has larger surfaces to finish.
Specific prices can vary quite a bit. Even the low buck route can dramatically differ, depending on where you get materials, supplies and purchasing habits. Vacationer will be about twice the cost of a Weekender, if both have similar quality materials and finish. Vacationer is a pretty ambitious build for the first boat building project on a limited budget. Many have been done as a first build, but far many more have been started and left uncompleted and disenchanted.
If 100 stock plans are sold, maybe 20 will get purchases of materials toward the build and less then 5 will get finished. The larger the boat, the more likely it will not get carried through until launch. This is typical of all home built craft, not just Stevenson designs and is especially true of low cost or free plan sets.
I just sold a plan set for my Lass design
to a fellow in Australia for 1,400 bucks. It's a substantial vessel (34' on deck) and the plans are very complete. With an investment such as that, it'll likely be built (this will be the third build of this design). A 50 dollar set of plans is little lost, in the big picture of things, so you don't feel bad if they sit on the coffee table for several years. For those that think $1,400 bucks is a steep price for a set of plans, consider the percentage of value. The boat weighs around 12,000 pounds and at $20 a pound will cost a quarter of a million to construct. This works out to be about 1/2 of a percent of the build cost and very reasonable. Most designers charge 3 to 6% of the value of the boat for a set of plans, so now it's looking like a real deal.
This said, a low buck Vacationer can be built for a little more then a well finished, good materials Weekender. Skill levels, and purchasing habits play a big role. Shopping around and buying in bulk can save big bucks. I just bought some lead the other day, having done so many times in the past. I get my lead from a local gun shop as #4 shot in 50 pound bags. It's easy to melt the pellets, easy to control how much lead you need and has the added benefit, of being easily mixed with epoxy and poured in a slurry into a mold, without the need of melting it. I can't get a 700 pound cubic foot this way, but I only use the epoxy and bird shot method for weighting dagger/centerboards, rudders or other small weight uses, where it's an ideal technique.
This is the skill level (experience) and buying habits I mentioned. I get the lead at near wholesale and use a technique that is fast and doesn't require the traditional melting process.
A beginning builder will have to develop these abilities. This (and other forums) board is a good place to pick up tips to save you some money, time and heartache, plus a fine place to cry over the latest setback, screw up or frustration you've encountered.
Welcome aboard Ryan.