The best way to do a check out one of these organizations is to talk to current members, especially the longer term members. There are a few ways you can find out who is in their membership:
1. Check their website, many groups list their members
2. Check their Department of Insurance License on their state's DOI license lookup, for most states, these groups have to list their members as producers under their license, that is for the states that require it
3. Do a Google search, many members list their cluster affiliation right on their website
I would call about 5 agencies in each group you are considering membership and talk to their principals. Yes it can be a lot of work, but keep in mind, making good decisions takes work. You can find a state by state licensing lookup and a cluster directory (the largest online) on AgencyEquity.
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