First and foremost one should make sure they are looking at an apples to apples comparison. Some carriers do not offer certain applications in their offering (i.e. LD minutes, web hosting with SEO options, some offer a couple of analog lines as a free add on to a full PRI, etc.). Equally as important is making sure that each carrier disclose additional taxes and fees. Some carriers will include certain taxes and fees in the base price while others will strip it out of the offering to make their product look more attractive on the front end. The difference in these taxes and fees can range between all included in the base price and increasing your bill by an additional 30%. A carrier broker that represents multiple providers is usually the best choice for sifting through these weeds for you so you can make sure you get the best deal although there are some really great independent agents that only represent one provider that can be good as well.
There are usually three types of carrier brokers: the telecom consultant that strictly sells carrier services, the IT vendor and the phone vendor. Sometimes you can get all three in one but there are also advantages to finding a guy (or gal) that specializes in one (or two). Each of these three types of brokers are usually a better bet than using a representative from a carrier who can be a crap shoot. Those reps are historically not around for the long term while the independent consultants, phone vendors and IT people seem to have a lot more longevity and have typically created a business based on referrals and reputation. If you need to find one of these types of vendors that you can trust, you can usually do well by asking your neighbor in the office next to you or someone you interact with in the business community and ask them whom they trust.
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