Common Colombian Boa females can reach lengths of 12-14 feet, but this is extremely rare in captivity.
I have physically seen three true 9 footers, and I owned 2 of them.
Have only heard of three 10 footers and have only seen pics of these.
Most common colombians these days - their growth slows down very much after 7-8 feet.
Anyway, a boa does not grow like a python... it won't reach 8-10 feet in one year, it will take more like 6-10 years..
A 4 foot Boaphile cage is enough for most adults in the 7-8 foot area..
I have successfully kept and bred 8-9 foot boas in these cages.
If this would be her permanent home, I would opt for the 17.5" high model with the shelf - I believe it's the 422D model.
This would be a big benefit for the animal.
Boas are fed what you decide - yes the somewhat easiest and most practical/convenient are rats, but they will also take rabbits, fowl, guinea pigs, piglets and more.
You can soley feed your adult boa rabbits, but to get it that big on only guinea pigs and rabbits will be a challenge.
You won't be able to find very small rabbits and guinea pigs as readily available and as affordable as Frozen Rats.
In closng, any boa, even those that seem to be 'the tamest' and even when handled by proffessionals, can bite, and like you said, it is 99.99% of the time OUR OWN FAULT.
With that said, chances are you MAY get bit again, and if that happens, will you be forced to get rid of her again?
That won't be a practical situation... this time around, you'll probably have quite a bit more money invested into her.
Just think about that before going out to buy again.
Hope this helped.
Thanks and take care - Joe
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Thanks and take care - Joe Rollo
'Tis not the stongest of the species that will eventually survive, nor the most intelligent, but the one most responsive to change' Charles Darwin