[Nick]

sence nobody else wanted to respond i will
that all depends what do you want to keep?
do you want corals?-If so you will need special lighing($70)
If you only want some fish and a few shrimps than its cheap.
the live rock in a 10 gallon would be 70 bucks if purchased off liveaquaria(thats were i would get it)
The salt would be cheap($40 worth would last you a long time)
No you do not need a certain filter
Oh i see it looks like you stated that you wanted coral. for the pricing on coral you can make it however much you want it to be.

Actually the lighting part is wrong if you want to grow corals. I also have a little ten gallon nano which i just recently got up and running. I have adequate lighting in my nano and it wasnt no 70$. It's lighting that I am able to grow most corals too. It's just a 50/50 fluorscent bulbs. I have the ten gallon hood so there two screw in type bulbs. They were about 12.00$ a piece. So its not to expensive

I cant really tell you if its easy or hard because I had it easy and already got cycled water and very expertiese live rock.

Nick