Have you asked your parents to buy you a hamster? First of all, don't beg! Well, some parents might get you what you want if beg, but it proves you aren't trusted. You need to prove you're responsible! I'd suggest you do a lot of research. Grab a notebook and check out the information I put on my sight. That should be helpful. Or go on other people's website and check out what they've got. Then, tell your parents you'll help pay, or even pay for all the supplies and stuff your hamster will need. Remember, hamsters take some responsibility to care for. Everyday they need fresh food and water, once a week they need their cage cleaned, and also they get sick just like any other pet would. Just because they're small, doesn't mean they should suffer if they get sick! They should be taken to the vet at least once every 6 months for a check up. However, some vets won't treat hamsters because they might be considered exotic animals, but trust me there not! They are like guinea pigs, rabbits, etc. Also show your parents you're dedicated to hamsters. You wouldn't want your parents thinking you'll not want a hamster anymore after a few months. I've had hamsters for years! I proved to my hamsters I was dedicated. You also need to make sure that if you have other household pets, they won't be able to get to your hamster. Also think about this, cages are quite a bit of money depending on where you purchase it. Your hamster may only live for a month, a week, a year, if it gets sick. I had a hamster that was a bay and pasted away after 2 months of having him. He got a disease called wet tail. So go over this page of my website with your parents, and I give you the best of luck on convincing your parents.
More information on wet tail:
https://en.wikipedia.org/wiki/Wet-tail
More information on wet tail:
https://en.wikipedia.org/wiki/Wet-tail