His own cage, or nothing
For a Syrian hamster, the boarding question is different from almost any other pet: the best service is the one that changes nothing. Ask first whether he can board in his own cage — transported carefully, set down, and left in place for the stay. A cage transfer at the boarder's end wipes out his scent markings, destroys the nest he built, and hands him a strange-smelling territory to defend and stress over; a service that insists on moving him into their standard cages is telling you they board by routine, not by species. Ask equally firmly whether he will be housed entirely alone: Syrians are solitary and territorial, and no shared or neighbouring-barrier arrangement that lets him smell and rage at another hamster across a divider is acceptable.
What a small-pet service should expect to do
Ask what daily care actually involves for a hamster in their care. The honest list is short: fresh water checked, his own food given the way you specify, a visual once-over in the evening when he is awake, and spot-removal of any obviously soiled corner. Deep cleaning during a short stay is a fault, not a virtue — say so, and ask whether they will leave his nest completely alone even if it looks scruffy. Also ask directly about handling: the right answer is that they handle hamsters as little as possible and never wake one in the day for a cuddle, because a startled, half-asleep Syrian is the one that bites.
Checking the room in person
Visit, and spend your time on the room rather than the paperwork. His cage needs a quiet spot — hamsters sleep through the day and a cage beside a barking-dog corridor or a busy reception makes that impossible. Check the cage position for draughts, radiators and sun patches crossing the bars, and confirm the room holds a steady, ordinary temperature. Confirm no cats or dogs have access to the room at all, including the owner's own pets wandering in. If his cage will sit on a shelf or rack, check it cannot be knocked, and check the lid and door of his own cage once more before you leave him — you know exactly how he tests them.
Food, wheel and the familiar
Ask whether they will feed his own mix from your supply rather than a house food, and whether his wheel — sized for a Syrian and solid-surfaced — stays in the cage; a hamster boarded without a wheel loses his main outlet for the whole stay. Leave a small bag of his used bedding with the cage so any necessary top-up smells of home. If the service wants a feeding chart, that is a good sign; give them his, including which treats are his and how many.
Leaving the instructions where they cannot be lost
A sheet of paper taped to a cage gets knocked off by day two. Handing the service a KinsLe Care Pass gives them his feeding routine, his waking hours, the leave-the-nest rule and your vet's details as a single clear handover they can check on a phone at the cage side — so the care you agreed in person is the care he actually gets at midnight on day four.