Personally I'd pass on both
Yeah, pass on the E-150 for sure, unless you know
for sure that all of your loads will be under 1000 pounds, no more. 180,000 miles is a lot on a Sprinter unless you know
for sure that the maintenance was meticulous and that all of the things that are going to break between 180,000 and 200,000 miles have already been recently replaced, which they almost certainly have not (wheel bearings, rear axle seals, alternator, water pump, belt tensioner, fan blower motor, lots of things). A little thing skipped here or there and the problem multiply and domino like crazy, and if those wear parts haven't been replaced already, you're looking at replacing them very soon, and if you wait until they break, you'll be looking at some serious tow bills.