New rabbit cage for going to bathroom:

Hi..we have a 2year old rabbit, names echo.he's so sweet. He is a free roaming rabbit in our sun room and loves it.

However, I have noticed he has been digging more in his cage he uses only for the bathroom sake and marking his terror right outside his cage as of late. Which I understand is normally...just annoying. I am thinking of getting a new cage, for him to use (we are using a small dog cage) with higher sides.

He has done well with his current cage but needs higher sides now. Any suggestions please.