A. Advantages of getting an RE license
1. Save on commission/fees for your house
2. Home builders may sign a commission contract with you based on your popularity/marketing reach, so you can bring clients to them
3. You will even get marketing commissions from loan agents/companies.
B. Disadvantages of getting an RE license
1. You have to be strictly ethical in keeping the party's interest at the forefront without being selfish, get the best deal possible
2. Study to get the licence (go thru the process), renew license, zero complaints
3. Disclose your RE license in advance for your houses for sale. Most of the times, this is a turnoff for buyers.
Bottomline
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Clearly, the advantages outweigh the disadvantages, at least prima facie.
That's why, we see a lot of new investors getting an RE license. How successful they are on capitalizing on the advantages is totally up to them. The ones that don't have an RE license, act as a principal, are thinking of just the A1 commissions (3-6%) OR are just not ready for the hassles. Another reason being, they make enough on their core transactions and don't have to worry about the peanut commissions. This is especially true for established investors.
For an investor, money comes first. Also he has to decide, if he's gonna make that money ethically or not, maybe in-between.