not just any old

not just any old + noun (not a typical, average or usual) — (это вам) не просто какая-нибудь...

Example 1: It's not just any old car. It's a Bently! — Это не проскто какая-то занюханная машинка — это бентли.

Example 2: Not just any old robbery, but one so unashamed and obvious that it is committed in broad daylight.

Example 3: In a boutique where one dress can cost as much as $60,000, it's not a problem, it's a crisis. "I love it when I don't like them." "You do?" "Yeah. Because I like so many of them, that it's wonderful if there's one I can eliminate. Makes life very simple. But understand, that's not just any old dress. It's conceived as a whole little — like a little poem." "Like a poem?" "It's like a story. Each dress is a story — tells a tale. It's a tale of rags for riches. (Whose Child...?; Some Like It Haute )

Example 4: "What are your favorite flowers?" he asked. "I'd like to grow them for you. " "You should know what my favorite flowers are by now." "I know I should, but I don't." They walked hand in hand to the garden shed, and there behind it was a galvanized-steel dustbin lid under a dozen or so bricks. "Well?" he said. "Roses," she replied. "But not just any old roses." "No, of course not," he snorted. "Well, don't think I'm going to tell you after that, she thought, but it's those small soft damask roses I like best, with their strong sweet scent and crumpled faces in old-fashioned shades of crimson. But that'll have to stay my secret now, too, won't it." (Greenleeves. Simpson, Helen)

cf.
[nothing to sneeze at]