I don't know if it would be cheaper, but after unlocking the second floor of the museum, you can rent out rooms and decorate them just as you would do with your house.
I think it'd be worth it. Towns with multiple fully furnished mansions are really cool, although they take a while to do.
You can make bells easily off of turnips, especially with the help of the Train Station here. I think there's an official turnip prices thread, and you can look there and find people where Reese is buying for 300+.
I think it'll be worth it in the long run. I've done it before with different-themed rooms and got lots of good feedback from it. Some of my friends were motivated to finish their homes after seeing mine. xD