Asterisk is a non-commercial, open source system, with all the advantages/drawbacks typical for this class of software.
If you have some people, skilled in Unix administration, programming and with experience in VoIP (so they will know how things should work) – you probably can build system which perfectly suites your needs with low costs.
If you do not have such people – then you might just loose a lot of time or a lot of money (by hiring external consultants) and still not receive what you need.
There are some companies, selling Asterisk-based commercial services/systems, but I do not have any experience with them.