Previewing apartments is something all good brokers should do. I realize, from personal experience as a buyer, that most brokers don't preview apartments that they bring clients to. In fact, many use the clients as the opportunity to look at more apartments.
I've made it a point to only show buyers properties that I have personally seen before, ie have already previewed. This saves the client time and it doesn't make the broker look stupid for not knowing the obvious things about an apartment.
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