BMW Repair: AC control head, blower motor resistor, independant shop

Question
I recently bought a 740IL.  Had it inspected beforehand and mechanic said it would be a $200 repair to fix to heat/cool system (wire loose). Went back after I bought the car to have it fixed and they told me it is actually going to be $1300 because it is the blower motor and blower motor resistor.  Took the car into a separate repair shop to get a second opinion and they explained that it is the resistor and the ac control head.  I don't know who to trust.  The AC control head seemed to be working fine.  All the buttons worked, the fans just didn't work.  What do you think?

Answer
I think that on things like this it's worth taking it to a BMW dealer.

Independant shops are much more likely to be "guessing" on things like this, and have to be able to cover their costs.  A dealer has more diagnostic tools at his disposal.

Also, if there are questionalle parts, the dealer can swap with one from stock, and if that's not it, return it. An independant shop has to purchase it, and that means you bought it.