I have actually done this before. When I was working at one of those petstores. Everyone knew me and my fiance would take the unwanted animals, and then try to find them a good home. So we got quite a few reptiles.
The big thing to worry about is vet bills. A lot of the animals that come into your care are going to need vetrinary care. If at least not just a physical and a fecal sample (which they will all need) but medications, x-rays, bloodwork etc. This can get really expensive. Some of them will have things wrong that cant just be treated at home. It can rack up high bills, and if you couldnt manage the finances then it would be irresponsible to do it.
I am still taking in aniamls now, although in much fewer numbers, but even still. I now have a good at a vet clinic that treats exotics, which is an amazing help, i can actually afford to take everyone to the vet, lol. If there is an exotics clinic nearby you should try getting a job there...even just as a kennel person..because they all get the same discount.
You can also get your rehab lisence, which just requires reading a book and taking a test (I believe). This can allow you to claim yourself non-profit and you dont have to pay tax on anything related to the animals. It also will allow you to apply for grants if you ever wanted to later on.
It is great that you are considering this because its definately needed. But dont do it unless you can provide the best care, and whatever is needed medically with these animals. It can get overwhelming, because once people know you will take them you may get quite a lot, so you have to be prepared.
Good luck with everything!
Keep us posted
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0.1 Bearded dragon
0.1 mexican Black kingsnake
1.1 Leopard Gecko's
0.0.1 Tokay Gecko
1.0 Blue Tongue Skink
0.0.1 Reverse Okeetee Corn
0.1 Anerythristic Corn
0.0.1 Red Tegu
0.1 Bullmastiff
4.1 Cats