siloz is meant to operate regionally, buying and selling in local markets; so a buyer must be within 25 miles of a seller (your location, when you’re logged in, must bee close to the seller).
You can sell for a silo in another region.
As long as a buyer and a seller are near each other, an item can be purchased. It is not necessary that sellers (donors of items) be near a *silo*, however; it is only necessary that potential buyers are near the seller (and this is, in fact, the only way a sale is possible – because of geolocation/georestriction).
Under no circumstances should a buyer coordinate with a seller to receive a shipped item.