Eos Rebel T4i + 430EX flash = washed out pictures

[WakkoWarner]

I do eBay listings for someone.  When I am out of town, someone else needs to take pictures.  So, we purchased a Rebel T4i at a pawn shop (barely had 1,000 shutter activations on it).  It needed a flash, as the conditions in the warehouse are not always optimal for taking pictures. 

So, we acquired a 430EX flash.  The problem is that no matter what position the flash is in, the pictures are always washed out.  We have a cheap Bower SFD35C flash that we were using with it (cost about $30).  It does an okay job, but doesn't light up the items enough (they are kind of dark, but never washed out like with the 430EX).

The camera that I personally use for taking the pictures is a Sony Alpha A65 with an HVL-F58AM flash.  I keep the flash angled one click backwards and the pictures always turn out fine.  Since I do not have experience with the Canon cameras, can anyone guide me as to setting up the camera and the flash to work together??  I am actually beginning to wonder if the flash is defective (it was purchased used), since once I take a picture, I can no longer adjust any settings on the flash until I turn it off and on again.

If anyone has any ideas or pointers, your input will be greatly appreciated.  Thanks in advance.

[WakkoWarner]

I asked the warehouse guys to take pictures of a few different items today, but they didn't listen.  So, I only have a couple of pictures of the same item.  Unfortunately, these pictures aren't nearly as bad as the ones in the past.  I will have them take some more tomorrow, so that we can see a few different items. 

[kvbarkley]

You have a reflective surface. You will need to get an extension cord to move the flash off camera or get two flashes at 45 degree angles. Or rig up a sheet as a soft box.