Rainbowair academy Long beach California. They have R22 at $168 per hour solo and I think Instructor time is $35 per hour. You will have to book in advance but they have online scheduling so its quite easy.
http://www.rainbowair.com/
If you call UKFT they will be able to sort you out cheap hotel as well.
http://www.ukft.com/
I had a FAA night Rating so i did quite a lot of my hours during the evening. Its a massive city and visual is superb so that helps with getting regular Time slots. Just make sure you have flown the city routes during the day so that you know what is actually in those black holes!
Hope this helps
Flash