aftermarket remote starters, keyless entry, and anti-theft devices are not recommended for Bimmers. They interfere with the electrics; and if you go that way... it's just a matter of time that you will have to uninstall them if you wish your bimmer electrics to work correctly.
Well I live in NY and there's this shop in Nanuet, NY Sound Concept. They are the only one I know who works on European cars extensively including BMW. I've seen them do a remote start for a Masserati with Smart Start. I believe the guy who owned it even had that car shipped from Colorado just for a remote starter since no one does it close by him.
I would try giving them a call and see what they can do for you.