Hi and welcome.
I live in Germany, and tried to pass tests at conservatories to become a schoolteacher. I passed two, but not good enough to attend.
But in the process, I found several criteria that might help your choice.
1) Entry test expectations.
Some conservatories ask for a second instrument; some ask for a very specific repertoire in your first instrument. I assume you want to study piano; and I know that e.g. the conservatory in Freiburg in Breisgau asks for two etudes; one of them by Chopin.
So: Find out what is expected. I recommend applying at more than one conservatory. If you have a bad day on exam day at conservatory A, you still have a chance to pass at conservatory B.
Some places are cheaper than others to live; but maybe you like the scenery of certain places. Do you want a big city or a small town? Do you like mountains? The possibility to visit France on weekends? Up to you.
3) Admission of foreigners. (EDIT: This is not from personal experience; I just thought about it)
I don't know if conservatories have policies about only admitting a limited number of non-EU residents. If you are from the EU, there shouldn't be a problem. If you're not, find out.
Hope this helps.
Edited by patH (05/08/13 05:45 AM)
Everything is possible, and nothing is sure.