I stop in at my taxidermist's place all the time... I'm fortunate that I work in outside sales and I just happen to have a hospital fairly close to where his shop is -- if you call 15 miles close! No, I don't think it would be that rude; they kinda expect it. Just don't get to where you're bugging them every month or so.

I used to have to pay half up front, but I've sorta got in the habit now of just paying when I pick it up. I've brought him enough work now that he knows me VERY well, and he also knows I'm coming back the next year... so he's really not worried about seeing me again or collecting.