In the first case there was one agent representing both parties. In the second it was one firm representing both parties. Either way it is Limited Dual Agency. The buyer and seller are represented by an agent who presumably knows more about the property than anyone else. The agent collects the commission for both sides of the transaction.
Life is good.
OK, that s the plus side. The minus looks like this. If the agent does not know his business, you are multiplying your ignorance. And if the agent is unscrupulous, the full commission may tempt him to bend the rules. Just be careful.