How much does a normal futon cost?

I can either rent a futon at the sharehouse I am staying at for $125 or buy one. Is it cheaper to buy one? Thanks

I presume you are talking about buying in Japan? You can buy a new futon set (shikibuton + kakebuton + pillow) for as low as 5,000 yen if you hunt around, and certainly easily under 10,000 yen. You can purchase by mail order, but if that's not an option and your nearest futon store or DIY centre is several stations away, renting for 10,000+ yen may seem more convenient and attractive.

Nitori offers a range of futon sets and other home necessities. They also deliver and even do cash on delivery. I've bought a few things from them this way that were too big carry on my bike and never had a problem with it.

If nothing else, it will give you an idea of how much various futons might cost.

http://www.nitori.co.jp/

Oh, sorry. My last link was for the corporate site. This one is to the online shopping.

I should have checked my links more closely.

http://www.nitori-net.jp/

Is it cheaper to buy one?

Depends a little on what is included (bedding, sheets, comforter, etc.), but you can definitely get cheaper if you go for a basic futon set.