I've been through this and I can only offer the following:
- make copious notes about all the disturbances and capture some audio/video if you can do it and it's compelling (lots of evidence is your friend)
- stay on top of the board and your property management company - they have the obligation to help you out (that's what you're paying condo fees for)
- make sure to read your condo by-laws carefully and be sure to understand which ones apply (most by-laws include provisions about quiet enjoyment and not disturbing neighbours)
- keep calling the police every time they party late at night
- chase down the owner and make it known that this a problem - depending on the kind of person they are, they may or may not be aware what's going on
If you've reached your wits end, contact a lawyer and get him/her to prepare a statement of claim for nuisance and ask for an injunction to cease the nuisance behaviour - this is a legitimate claim under civil law and you can claim significant damages for loss of enjoyment and reduction in value to your home. In my case, I actually reached this stage and prepared a complaint against the owner and the tenant for more than $100,000. While my lawyer felt that I had a strong case, we never actually filed the complaint. I simply prepared it and sent it to the owner/tenant and told them that if they failed to stop the behaviour, I would file and pursue it. Technically, the owner is ultimately responsible, but it's good to include both parties on the complaint. I was prepared to file the complaint and pursue it if I had to (would have been expensive), but I didn't need to. The very threat of something like this got everyone's attention (I also provided a copy to the management company and the board) and things started to happen.
It's worth pointing out that litigation is definitely the "nuclear option", but in my case, I was pushed to the brink. It sounds like you may be in the same spot, so you might want to consider it. Getting the statement of claim prepared is not a complicated or expensive exercise, but it will cost you some money (unless you happen to know a litigation lawyer who owes you a favour).
Hope that helps. I feel your pain and frustration and I hope things get better.