Sadly, this is nothing unexpected. At the shop I was at we would VERY frequently have customers come in after purchasing a BMW from a dealer as you describe. They always complained that BMW is a terrible, unreliable brand... we always told them that they hadn't really paid for their BMW yet. Also reminded them we do PPI's the next time they wanted to pick up a car from one of these dealers.
You can't get a reliable BMW for $3000 that needs nothing. Expect to put at least that into it after purchase if you are having someone else do the work to make it something worth driving. That's just a general statement ylwjacket, not directed at you. You are bringing this X back from neglect which can often be a rather frustrating process of repair this and wait for the next issue to let itself be known.