GREENWATER, Wash. — Some neighbors simply cannot grasp the concept of a property line. There they go, again, cutting through your yard. Sneaking a peek in your windows. Sniffing around for free vittles. Letting the young ’uns hoof it all over tarnation.

Cases like that, you have to set some boundaries. Special case in point: when your etiquette-oblivious neighbors are enormous elk.

“They’re safe in here, and they know it,” Pam Willis says of the blissfully peaceful Crystal River Ranch community near Greenwater, where she lives with her husband, Chris, in a strikingly double-sloping home that eases elegantly into its surrounding forest. “They cross the river pretty much year-round.”

As delightful as it is to dwell among those molting roamers — along with the rest of the resident White River wildlife — it’s probably not the best idea to invite them in. So, right off the bat, the Willises’ horizontal Zen-like entry courtyard not only transitions from outside to in; it also forms a gentle elk periphery.

Once inside the courtyard, though, it’s all the Willises’ — and they’re especially invested in this particular habitat: Avid skiers, hikers and cyclers, they had a weekend cabin down the road before discovering this 20,000-square-foot lot (and an empty nest) after their son left for college. Also, they served as their own general contractors, completing the two-bedroom, two-bathroom house in seven months, within budget.

“Chris (a civil engineer) has been in the construction business,” says Pam, who’s semiretired and now “dabbles” as a ski instructor at stone’s-throw-away Crystal Mountain. “He knows how to manage a site, so we did a lot of the gruntwork ourselves: wrapping the house in insulation, nailing the subflooring, weatherproofing the exterior — a lot of labor-intensive stuff.”

Going in, they had a Crystal-clear vision (one level, courtyard, open, light, just big enough for two), a tight budget — and an architect, Robert Hutchison of Robert Hutchison Architecture, who embraced both.

“Going to an architect, we thought, ‘Would one even take this on, knowing our budget was so limited?’ ” Pam says. “But it was a great process. Rob kept reminding us it was a process.”

Hutchison says they went through 10 or more design schemes en route to economically, efficiently and beautifully meeting the site’s restrictions, and the budget’s.

“The goal was to try to keep things simple and celebrate one or two architectural features,” Hutchison says. “So we focused on the double-height space, exposed structure and steel. It had been bigger at first, and we had to scale down. But the original resides in the final scheme, and it’s more efficient.”

There was room for the occasional splurge, he says (steel panels on the fireplace mass, large tiles, custom-run wood siding, a metal roof rolled on-site), amid more-economical choices that maintain architectural integrity (wood cabinetry, Sheetrock, no fancy custom wood base, plywood and Glulam, stock window sizes, not quite as much concrete as Chris would have liked).

A lot of elements required no compromise at all: Chris did get the birch he wanted, on the kitchen island and in the master bedroom, along with translucent glass in the master bathroom (last thing you need is a peeping elk with Instagram). The two bedrooms are at opposite ends of the home, so guests (or a visiting son) have their own lovely space. Hutchison “kept pushing” for the black stain on the exterior Western red cedar siding, and got it. (Once it was up, he says, “Chris called and said, ‘Rob, it’s beautiful.’ ”) (It is.) And while the 400-square-foot garage doesn’t actually hold a car, it is the perfect space for bikes, skis, ski tuning and storage.

From the defining courtyard to the outdoor patio on the tippy edge of elk-land, the Willises’ home/habitat is all them, and all theirs.

“With the budget, they did an amazing job, and a hell of a lot of work as homeowners and contractors,” Hutchison says.

“With Chris’ background, we knew how much money these things cost and how much we could save,” Pam says. “Plus we did like doing it ourselves. There’s something about doing it for your own home.”