If I am not adopting an animal from a rehab/rescue facility or a friend, specialty stores are a close second. If I go to a bird-specific store or a tropical fish store and I notice they are always busy, I can assume they are doing something right. Knowledgeable staff, concentrating on one taxonomic group of animals will make your experience enjoyable and end in a healthy acquisition.
No matter where you acquire your next animal, getting a free veterinarian visit with your adoption, plus a file on the animal’s life history (birth/hatch date, vaccinations, food, favorite toys, etc.) should make you feel more secure in your new critter companion.
Giving up your pet can be very emotional. Depending on your circumstances you can be fussy about who adopts them. I have sold pets to friends, at poultry shows/fairs and through newspaper ads. After keeping a pet snake for years, I went abroad for college and the original person who gave me the snake gladly took her back.
Selling or giving a pet to a friend has a lot of benefits. In your clause you can state that you can take that animal back at any time and find it a new suitable home, you can check in on the training/well-being of that animal, and you might be able to visit and play. Whenever I sold an animal I tried to make a connection to that person, so I could see how the animal was doing later on.
One of the most positive experiences I had was placing an ad in the paper selling baby cockatiels when I was a freshman in high school. The calls quickly came in and I made a few appointments for people to visit first and then decide when they were ready.