First thing is this. You weren't ripped off. Let me guess you got around a 100k miles on the 4.4 right? CV boots are a normal replacement item. The coolant leak is also not rare at your mileage. Again the alternator also is not uncommon either. Tail lamp is a known defect for all our x5's. Basically everything you mentioned is known to fail at higher miles. You may feel slighted because you are having to fix these all at once. Your X is not a lemon.

Anytime you buy a used car with high mileage and age on it, you have to be sure of everything. You should've taken it to a mechanic to get a diagnosis before you bought the car. He would've been able to identify most of the issues you state, if not all. If you try to take it back to the dealer you bought the car at, they will laugh at you while you drive off unhappy. Your biggest issue was not being thorough before buying the car. The repairs your X needs are not abnormal at this stage of its life. Furthermore, I suggest you taking it to an independant mechanic shop who is familiar with BMW's to do the rest of the repairs. An alternator can be bought for 250 bucks. It could have been installed for a couple hundred more for labor. Price shop, be smart. Good luck.