Hamster in a 20 gallon?

[Licorice@Carmel]

My hamster doesn't like being disturbed (who does?) and we have a loud house, so we were thinking an atleast 20 gallon tank for her, but we don't know prices.  She lives in this, but she doesn't use third story, and only uses second story for water. 

http://www.coastcages.com/catalog/index.php?main_page=product_info&cPath=4&products_id=45

Anyone know if this is a good trade? If we do get a twenty gallon, we would probably sell it at a garage sale or something, its terrible for my little tinkles.
Anyways, question is
1. Price for 20 gallon and topper? (just screen)
2. Where can i find?
3. Stick with cage or go with tank?

[Summer_Rat]

Is it a 20 gallon long or a 20 gallon tall? Or what are the measurements. Really a 20 gallon tall is too small for hamsters but it is considered the absolute minimum with a 20 gallon long being much better.

If you don't mind cleaning it then I think it is fine.

[Licorice@Carmel]

I did the math and either way she has atleast the same amount of room but it would be long .