>> I'm not new to snakes but this will be the first large snake that I will keep alone.
Hi Heather,
Without knowing your situation, age or what other snakes/reptiles you have experience with I have to offer a word of caution since you said 'alone'.
I do not recommend handling a snake over 8' without someone else in the home (safety net). SFEs and other accidents happen and when dealing with a large constrictor, it's usually safest to have someone to call to for help (happened to me twice in 10 years - both SFE). When I lived alone, I always asked a friend to come over that knew I would be dealing with my large boas, just in case. I know the chances of something really bad happening are minute but better safe than sorry IMO.
So with that said I would recommend one of the dwarf BCi (hog isle, crawl cay, etc), they have the boa behaviours and looks and tend to max out under 6'. Another good choice may be a rainbow boa, they are stunning beauties. Or for something more exotic, an Amazon Tree Boa, Green Tree Pythin or Emerald may be more up you alley. The options are basically limitless.
Good luck with whatever you decide to get!
-April

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'There is a very fine line between "hobby" and "mental illness."' -Rainshadow