Hi Rae, my 0.02$
"red tailed boa" is a loosely used term. There are several subspecies of boa that are called that. Most typically refering to Boa Constrictor Constrictor (BCC) and Boa Constrictor Imperator (BCI). The BCC is considered the "true" redtail duh, they have the reddest tails. BCI's are commonly referred to as redtails as well. Does make it confusing huh? I have many BCI's but do not have any BCC's. Most likely you're inheriting a BCI. Have you seen it? you could compare to pics on the forum and the sale ads. If you have a pic, you could post a pic up here and the group would give opinions on it's locality.
Boa's are "new world" (the Americas) and are live bearing.
Pythons are "old world" Africa/asia and are egg layers.
Your boa will need a larger enclosure, probably 2' x 4' minimal. Or even larger for a big female. They like it nice and warm, mid 80's with a hot spot in the low 90's for basking.
for more info, try www.riobravoreptiles.com/care_raisingboas.htm
>>I'm inheriting a 'red-tail boa,' which I'm very excited about, but I had always thought that 'red-tail boa' referred to a particular type of snake. Melissa Kaplan makes that term seem awfully general. I'm just looking for an explanation of all things boa; does a 'red-tailed' boa really exist; what's the difference between a boa and a python; and any other resources for somewhat of a newbie. My experience is with kings, corns, and frogs.
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>>Two cats named Beatrice and Theta
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>>plus a cornsnake named Nora
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>> equals nirvana without needles for a girl named Rae
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Thanks,
Dave Colling
www.rainbows-r-us-reptiles.com
0.1 Wife (WC)
0.2 kids (CBB, selectively bred from good stock)
LOL, to many snakes to list, last count:
11.24 BRB
10.16 BCI
And those are only the breeders 
lots.lots.lots feeder mice and rats 
nirvana without needles 