If the pictures must be configurable, you must either host them somewhere (but I would avoid cross-site problems), or put them in the database. You could use the eSpace's img directory, but since everything's hosted in the cloud, you don't know what'll happen to it. For temporary images it's ok, but I wouldn't use it for permanent ones.
As for the maximum database size available in the personal edition, see here how to check.
As for the maximum database size available in the personal edition, see here how to check.