Use common sense and be careful. For example, only give a bird a new toy when you are around to assist if problems arise, and remove the toy when you need to leave the house. Keep fraying rope toys trimmed back to avoid the potential of soft threads entangling toes, necks and feet. Keep birdie toenails trimmed to a reasonable length, because snagged toenails are a common source of injury in caged birds.
Regarding out-of-cage time, if a parrot lives in a sufficiently large enclosure that allows free wing flapping, swinging and exuberant play, I don’t think it needs as much time outside its cage as does a bird with less room. However, if the enclosure isn’t large, I can’t imagine how anyone could calibrate “sufficient time.” I have heard it said that parrots need X number of hours of out-of-cage time daily, but I have no clue as to how those numbers were attained. After all, how many hours a day does a child need to play outside?
There are too many variables (including species, age, sex, etc.) to be able to draw sweeping conclusions. Some avian species are by nature more active than others, and many small birds, like finches, are more energetic than some larger psittacines. However, I do know that if your birds are easy to handle, the likelihood increases that your bird-sitter will enjoy allowing them out of their cages. Perch training is especially important when pet-sitters are less accustomed to parrots, because it allows anyone to easily move the bird around without risking a bite.
Will your birds be angry with you for leaving? I have specialized in parrot behavior for more than 15 years but still cannot tell you what a parrot is thinking. I do know that some parrots appear to go through something like a “punishment period” when owners return from a trip, but I have never heard of this behavior lasting more than a day or two. With birds that seem to hold grudges, owners should watch the body language and be careful not to force interactions until a bird has settled down.
From my experience of boarding parrots in my home for more than a decade, I doubt your birds will be traumatized. Parrots are adaptable creatures that do adjust to change, despite all the old-wives tales to the contrary. If they were not flexible, they would not survive in the wild.
In my experience, inflexibility has more to do with how an animal is socialized rather than its inborn nature. Owners who try to protect their birds from change inadvertently make them more vulnerable. Change, after all, happens. Owners who socialize their birds to other people, take them places and let them have slumber parties with trusted friends end up with parrots that adapt easily to changes in their routine.
In the years I boarded birds, no bird stayed upset in my home, started plucking for the first time, or even lost an appreciable amount of weight. I don’t believe they suffered while staying with me.
My boarders often adapted better than some owners did, though. Many clients phoned repeatedly during their trip, obviously worrying profusely about their birds. They often confessed on their return that they were initially hurt by the realization that instead of their birds pining away during their absence, the birds played, flapped, screamed, ate and had a great time!
Business trips are often a fact of life, and according to experts, vacations are necessary for emotional health. If you allow your parrots to tie you down with guilt, the odds are good that you could end up resenting them, and this is not conducive to a long and happy life together. I disagree with those who believe your life must revolve around your parrot for you to be a “good owner.” Parrots are long-lived creatures, and we want to enjoy them over the long haul. To do this, you need to have a life, too.