$1000 over invoice is way too generous!!!
$0 over invoice should do just fine.
I usually negotiate $0 over invoice, then let the dealer have $200 over just to be nice.
Go to truecar.com and build your car with options that you want, then print "dealers invoice" and put that print out on dealers desk when negotiating. If no deal, go to another dealer,- there are dealers that will be happy to sell you the car at invoice or close to it. Usually the bigger dealer corporations are easier to negotiate because they have a high turnover and make money on volume.
I got my M3 at BMW of Tenafly NJ, they are a part of a huge Penske Corp., so getting invoice deal was easy. My sales rep was Michael Lyubimov, cool guy, worked everything out with me over the phone and via e-mail, I never had to go to his showroom and sit down at his desk negotiating,- the only one time I went to BMW of Tenafly in person is to pick up my M3!