While the first two appointment types require you to go through the steps of choosing a date and time for the showing, the third (View Instructions Only) provides you an easy way to see the instructions and see the property.
When you choose an appointment type you can see a description which indicates the type of home that may fit each type the best, but they can be assigned to any listing.
Permission must be obtained from ANY of the designated listing contacts (Owners/ Occupant(s)/ Listing Agent(s)) before the appointment request can be confirmed. Typically used for occupied homes.
Courtesy Call or Go and Show
Appointment requests are documented and immediately confirmed. Typically used for vacant homes on lockbox.
View Instructions Only
The showing agent will immediately see any notes provided by the listing agent. The showing agent will not be given a calendar to select a date & time.