What is the daily/weekly/monthly maintenance?
It depends on what kind of hamster you have, and the cage size/type. For instance, my male syrian is litter box trained, so I clean out his litter box every day or so. You also have to give them fresh food and water every day. Since Max is litter trained, I don't have to clean his whole cage more than about once a month.
What type of hamster is "best" and why? What type do you have?
I have a male syrian, and that is what I would recommend for a first time hamster owner. Sure, you can only have one syrian, but their personalities are awesome (well, the ones I've had) and males tend to be more cuddly. Females, IME, are more moody, and aren't very interested in you. Plus, syrians tend to be more laid back and are big enough to hold on to. That being said, I have met very sweet, cuddly female dwarfs.
What should the cage size be and what should be in it?
A lot of the hamster cages on the market aren't very suitable. Dwarfs can usually get out of cages with metal bars, and syrians can get stuck in the plastic tubes. I make all of my rodents' cages out of plastic sterilite bins. Max is currently in a 30 gallon, two level bin cage. Here's a list of what should be in it:
Water bottle - not a dish, as this will just make a mess
Food bowl - I prefer ceramic
Bedding - DO NOT use cedar or pine, only aspen or wood pulp (carefresh, yesterday's news)
Wheel - I've found that an 8" wheel works best for syrians
Toys - hamsters, like all rodents, need something to gnaw on to keep their teeth worn down. Wood chews from the pet store, popsicle sticks, and dog biscuits work great. In addition, toilet paper tubes, newspaper, walnuts, and Kleenex are all great hamster toys to help keep your little beastie entertained.
Nest box - I use small cardboard boxes, like tissue boxes
Litter pan - If you want to litter train your hammy, get a triangle shaped litter pan that goes in the corner, big enough for the hamster to fit inside
Litter - don't use the same bedding you use for the rest of the cage. I use rabbit/guinea pig pellets
Hammocks - I also like to give my boy a hammock or two to sleep in. You can google search "rat hammocks" to see what I'm talking about. I crochet most of Max's, and he loves to rip them up and make them into a nest. 0_o
Would you reccomend a hamster?
I think hamsters make wonderful pets, provided that you're committed to giving it the best care you can for its whole life - not just pamper the critter for the first two weeks and then get bored with it. Trust me, its not just 7 year olds that do this, adults are equally as guilty (LOL, trust me, I've worked with an animal shelter for 6 years, and I've seen the poor creatures that get handed off because owners just "don't have time any more")