Like any animal, hamsters may fall ill. When they do, they need to visit the vet, and it's good planning to have some form of pet insurance rather than having to pay for an expensive treatment out of the blue.
If a hamster is unwell, a trip to the vet is necessary
The price of pet insurance varies. Depending on which plan you go for, there will be a different excess cost (an excess being how much you need to pay if you make a claim). This amount will not be refunded by the insurance company. For example, if your pet requires a treatment that costs $75 and you have a $25 excess, then you will pay $25 of the $75 cost.
Another option is to save for any potential vet bills by putting aside some money each week. This should prepare you for any hamster health problems in the future.