When you buy new instruments, as I did with my Red Special, generally you don't have a problem as long as it's a reputable seller and they know how to ship the instruments properly. When you buy used however, make sure they have pics of it from all sides that are clear so you can really see what you're getting. I bought a Schecter Gryphon from Ebay, and it was listed as in near mint condition. When I got it, the push/pull tone knob, with the shaft, would actually fall out of the pot, and it had a ding down to the wood by the jack, and another small dent on the other side.
Know where it is now? At a luthier getting the blemishes fixed. I will fix the pot and do the setup on it myself, I just don't know how to do finish work. So basically, that's going to cost me an extra $90 or so to have that stuff taken care of. Why did I keep it instead of sending it back? Because I got it for $175, and the rest of it was actually in mint condition, leaving me to wonder if these blemishes happened in shipping. The tone knob couldn't have, but the blemishes could have easily considering it wasn't packaged as well as it could have been. I literally had the guitar for about a week before it went to the luthier. That was last October 22nd. That's the problem with qualified luthiers. There aren't many of them around, and the ones that are there are absolutely swamped.
So definitely, take all the advice you got here, and make sure you know what you're getting before you buy, including all disclosures of any issues, be they blemishes, electronics or whatever. Willowdale and Longhair pretty much covered everything.
