Q: it can be homemade
A: Check Michael's Arts and Craft Store http://www.michaels.com/art/online/home They usually have 40%-50% off any item coupons in their weekly flyers. If that is still too much, goto a hardware store like Homedepot and buy the raw materials to build a canvas. You can even try to ask one of the store workers to help you build one instore. http://www.ucsart.com/index.php?p=How_To/How_to_Assemble_a_Stretcher_Frame