Extras such as extra beds cannot be mapped to extras created in Sirvoy. The price for them should be set at the channel. However, when an extra bed is booked at a channel, it will show in the booking in Sirvoy and the booking value will include the price for the extra bed(s).
The settings for the maximum number of guests set in Sirvoy should not include any extra beds the hotel might sell for the room type.
A room type called “Double room” has room for 3 persons, including the extra bed. Still, if it is used in the connection to a channel, the room type should have this setting in Sirvoy:
Number of guests: 2
Max. number of guests (incl. extra beds): 2
In this example, the occupancy setting on the channel must be set to 2. The extra bed setting on the channel is made in addition to this and will make it possible to book the room for 3 persons. On some channels such as Expedia, this will mean that the maximum occupancy is set to 3, but the third bed is specified to be an extra bed.
Since you might like to present the rooms differently on your home page booking form than on the channels, you might like to set up duplicate room types and use these uniquely for the channel(s). Please read more about it here.