Looking for a very lightweight, umbrella type stroller for a 4 yr. old that will fold up easily and be easy to carry if not in use because we will have another regular stroller with us too (for the baby). Prefer one with some kind of cover from the sun/rain. Now the big thing...would like to keep the cost down to under $50.00. Am fine with buying used-just want something good that will stand up to all the parks!