Looking to buy, need pointers.

I have been in the market for a cargo van recently and have foudn one that I am interested in.
2004 Ford E350 Super Duty 5.4 V8, 197K miles, orignial owner (small biz who is updating their fleet), asking $4600 OBO.

Any thing I should be looking for when I check it out? Known issues? Thanks for your input.