Yes. Unless agreed differently with Globexs, a Globexs owner on a Premium or Superior plan can always refuse a booking.
If Globexs receives a booking request for an apartment, the owner will be contacted to agree the final terms. Although Globexs carefully filters every request, and only presents serious candidates, sometimes an owner is unable to accept the booking, for whatever reason that might be (for example: the owner needs the apartment for personal use).
Because Globexs does not demand exclusivity to the owners, we have no 100% control over the availability of the apartments. For every request we double check the availability with the owner. On the other hand, by signing the Globexs intermediation contract the owner agrees to inform Globexs at all times when the availability of his apartment changes.
