If you "almost" own it, I assume you haven't actually purchased it yet. If the transmission is suspect, which any automatic with 260,000 miles would be, especially with burnt tranny fluid, then DON'T BUY IT! Do you know how much its going to cost you to have a rebuilt tranny installed? Around $2k, maybe more. Why would you want to buy this car? With that many miles it probably needs, in addition to the tranny, new brakes, new radiator, new suspension, etc., etc.
'84 300D, 173k
'90 300CE, 162k