My 3 guinea pigs have full run with the rabbits in the summer!It's 10ft by18ft open,but there are lots of places to hide and shelter.Use small "dog baskets" plastic ones,upside down just right size!In the winter i use my daughters play house,but only when it is warm and the grass is dry! I used the grids when i first got Boris because he hadn't been neutered then.Used small cable ties,using the grids 3 along,2 wide with lid don't put any on the bottom,so not too hurt their feet!Make sure that cable ties are tight so to stop sagging!Good idea is to use metal tent pegs to secure down.Stops guinea pig picking the run up,keeps them safe from cats,dogs etc or if you have a small hutch put the run on the front,make sure that the guinea pigs cannot escape under and out from under the hutch..again using the tent pets to secure down.Also easy to take down in the winter time,just cut the cable ties off! P.S make sure you trim the long bits off the cable ties,leaving no sharp pieces, incase guinea catches their eyes etc
