5 pages about the building plan and almost nothing about the business plan means we have to expand the discussion a little bit. Please take this post as helpful advice and not trying to be negative.
Doing a saw shop with second tier brands, (everything besides Husky and Stihl), is very very difficult to accomplish. A lot of variables need to fall into place for it to work. A lot of guys on these sites try some form of this, but putting up a new building is a more serious investment, that entails a little more risk. It all comes down to how many dollars are you going to need and where, realistically, they are going to come from. Even with Husky or Stihl, you have to really be in timber country to just do saws.
It takes a lot of saws to add up to some dollars. My rep tells me I'm the biggest saw dealer in his territory, (82 dealers). Proud of that, but without Exmark and Gravely, we'd be a real different business. If no one is running Jonny or Dolmar in your area, it takes a long time to gain momentum and you'll have to sell cheap to get guys to bite. If you make $50 a saw, you have to sell 100 of them to generate $5000. That's a lot of saws for a Jonny/Dolmar dealer. Selling at retail is slow going for a new business. One of the keys is the more saws you sell, the more guys you have coming back for bars, chains, etc.
I guess part of the formula is where you are in life too. A young guy that needs it to really take off and make a living raise a family sort of thing? That's a much higher mountain to climb. If you're older, semi retired, and much of life's debt like a mortgage, kids education, is behind you. In that case the business only needs to "pitch in" and can succeed at a much lower volume.
What's your competition? Is there a good strong dealer with a great reputation, or a couple of dealers who are pretty much incompetent? The weaker your competition, the wider the door is open for you to capture their customers. A real strong house is pretty hard to chip away at. But if there's a real need for a shop that knows what it's doing, that's the best open door you can have.
Is there a good pro market where you are? We are lucky in that we literally live in a forest. But our big volume comes from both loggers and tree companies. (And landscapers for the other handheld stuff) In all 3 cases, those customers consume huge amounts of parts and accesories. They beat up, blow up, break, run over, and wear out equipment that needs to be replaced. A pro guy can use up a saw in 2 years vs a homeowner owning one for 20 years.
Contract work could add some nice dollars in the shop, and you'll need the extra work in the early going anyway. Many of the "big dealerships" don't have a decent 2 stroke guy. Some don't even have a bad one. LOL. A good example would be a John Deere store that took on Stihl. Some are very happy to sub out the saw work that no one in their shop is any good at. And since most of the big ag dealers have real high labor rates, you can get your full labor rate on doing their work. It's usually not a good idea to score points for the other team but: What will happen is, the word starts to get around that, "you might as well just drive over to Carl's" and once those customers are actually pulling into your lot, they'll be buying their parts and accessories from you. Everything has to grow from somewhere.
Plus, an arrangement like that gives you a connection to get Stihl parts for your own customers. (And Jonsered will supply most Husky parts.) Reality is that a new shop has to work on whatever comes in the door, and your going to need parts for those saws. The aftermarket stuff helps, but it can only get you so far. Who, knows, at some point Husky or Stihl might come knocking on your door, but it will take a few years of establishing yourself before you can make the large investment that is the price of admission with those two lines.
The building is derfinitely a decent size. Big enough that you can consider whether or not you want to get into mowing equipment. Yeah, I know, not as fun as saws! But it can add some dollars to the bottom line. From the pics, it sure looks like there's plenty of grass in that pretty country, so it's something to consider. Jonsered has a mix of Husky tractors and zero turns that would allow you to test the waters there. And Jonsered distributors don't seem to force it on you like Husky does. I mean if that business is there you have to think about it, right?
Don't know what inspired this long winded rant, but I'd like to see it succeed just like everybody else, so just sharing some thoughts.