Most real estate agents like to preview. Previewing homes is a way that agents can prepare ahead of time for clients by looking at the homes their buyers like. This way a long list can be narrowed down to just a few, or a home that has an odor or a hidden problem, like a missing air conditioner, can be spotted before hand. They agent can determine if it is still appropriate, based on their buyer's preferences, or buyers may decide not to look at the home, or could reconsider the priority of it.
Obviously, previewing saves time, but how does it save money? Well, time is money! Also, if a buyer is taking time off from work to look at homes, that is time saved and money earned. If the buyers are a couple and only one of them is able to look, it can be useful to have information ahead of time, so they can decide together if they still want to see it.
If you are a busy buyer, ask your agent if previewing properties can save you some time (and money)!