The tank looks good and i would not worry about the glass strips on the bottom as long as it is like what glass cages has. I do agree with some, the stand and canopy will need to be redone. If you are good with woodworking and can refinish the stand (rebuild) and canopy then it seems fair to me. It does look as if there was some leakage of some sort.
Before you buy it, make sure they have it filled up with water. Inspect all seams with a papertowell and make sure nothing leaks. Take a mag12 pump with you to drain the water, should not take longer than 10 min to suck all that water out with a mag 12. Good luck, coming from someone who just moved the 300 from lubbock, i would NEVER do it again....i live and learn. Just think if you bought the tank for 650, spend 200 in gas and 10 hours on the road...you are already at 850. By the time you refinish stand and canopy 2-300 and add lights 5-600 you are at 16-1700. It all adds up quick. Look around for local tanks with all of the goodies, they pop up before you know it.