Still working on targeting with my 4 budgies. They know how to get in an out of the cage on their ow so i allow the to fly free until they get tired or hungry. The only problem is, the first thing they do is fly to the curtain rods and chew on the wall paint ant the metal. I hate alarming them but the only way i can get them to stop is by making a loud noise to catch their attention. I have put clothing pins on the rods for them to chew on but the paint just seems more interesting.I'm also very concerned about the paint contents considering this is a very old house.
Since it's possible that there's lead could be involved, I'd find a way to block off their access to the wall (area where the curtain rods join the wall. Clear acrilic plastic sheet
could be cut and screwed into the wall on those areas. Alternate temp fix would be to place some strange objects (experiment with something they fear) on the rods to keep them off. You may have to change them out with new objects, once they get used to them, and create a hanging out spot closer to their cage but still higher than their cage. Good luck.
Phil is absolutely correct.
You need to find a way to deter them from chewing on the paint and the metal rods.
Lead and other ingredients in paint can be extremely toxic to your budgies as can chewing on metals that contain lead or zinc.
Heavy metal poisoning is an issue that you don't want to face!