I know a lot of people that started with Colombians and are still doing great. How big is the specimen right now? There is no set length for any species, haveing maintained a small breeding colony of 30 boas at my old job I can tell you now that size varies considerable among BCIs (Colombians), I have a male that has maxed out at around 6.5ft and my female might just be flirting with the 9ft mark right now, I have not measured her in a awhile. Care is pretty straight forward. Handeling is a mix, some will sit with you, but most are quite active. Hope that helps, if you want more advice on husbandry just let me know.
I found a deal on Craig's list. Someone owns a 5-6 foot Colombian red tail boa that they want to get rid of. They have had it for 7 years. It comes with a 3 foot long cage. Debating on if I should do it? It's a good deal.