The pair got going in February last year, after purchasing the land from a local dairy farmer.
"It's a one-off subdivision, nice and quiet."
The Aitchisons previously ran a five-star bed-and-breakfast in Mt Victoria, Wellington, and have treated this as their retirement project.
A project manager by profession, Mr Aitchison supervised the construction.
He said stays were offered only on a two-night or more basis.
"We offer a hosting experience, not an accommodation experience.
"We suggest people arrive early afternoon, early evening, settle in, get drinks and nibbles before they do anything else.
"We do the meals, we give people a pleasant, relaxing experience." Depending on their guests' plans, the couple can organise activities from wine trips, town visits or full-on tramps into the Tararuas.
Mr Mark said he lived "just over the fence" from the Aitchisons.
"They have certainly raised the tone of the neighbourhood."
He thanked them for having "such confidence in Carterton" that they built their lodge here.
"You've clearly got class, talent, business acumen and skill. We are just over the moon, this is only good for Carterton as a whole."