Depends on the set. Unless the thing is very rare or unusual, I would much prefer (put a greater value on) a repaired set, so long as it was done well (no tape, glue stains, etc.).

My main reason for asking was my recent purchase of a Marvel Super Heroes Advanced Set. I've been trying to find one at a reasonable price for over a year now. Most are going on eBay for $100 and up, so when one came up on FB for $30, I started bidding, I dropped out when it topped $50 (yeah, I'm broke most of the time...) However, a month or so ago the seller contacted me and said that the original buyer had fallen off the map and was I still interested in it at $50? Uh...Let me think about... YES!!!        

Fast forward and I received the whole package a couple weeks ago, but the box is blown out. The cover is essentially flat when it's not on the lower part and the corners are starting to rip out. Hmmmm... Look on YouTube, see a MULTITUDE of different ideas of how to fix it. Bottom line, I found one where the guy fixed board games all the time with an angle brace made from a PC slot cover and some wood glue. Look around in my desk and I've got some small metal straps that I could bend into a 90 degree angle brace, grab a few bull-dog clips and my wood glue and now the box is really nice and solid. There is some evidence of glue on the corners, but overall it looks MUCH better. Bonus: The seller included the books and maps from the Revised Basic Set in the box, so now I have the Original Marvel Super Heroes set, the Revised Basic Set, AND the Advanced Set! I'm a happy collector!