Guinea pig fleece bedding- replace costly shavings with washable fleece, lined with absorbent terry cloth (towel). Also made wee wee pad for "that corner" , with several replacements, and cuddle bed, pillow and blanket. Lots of cute patterns of fleece out there to mix and match.
How Much Do Guinea Pigs Cost | http://abyssinianguineapigtips.com/how-much-do-guinea-pigs-cost/ A really detailed article covering the costs needed to get or maintain a guinea pig. Includes three calculators, as well as a section on how to get free or discounted supplies.