I'm new at chicken raising and I'm trying to figure out if my lawn will get ruined (I live in the city) if I keep my free range chicks in a portable run and move it around. How often should I move the run? I'm not as concerned with the poop as I am about having my grass ruined. I also need to know if I build a 3' x 4' run for my 2 chicks, will this be large enough for them and how will I get them in and out easily? I'm older and can't lift much weight which is why the run would be smaller. I would be very grateful for any ideas or suggestions.