I'm afraid she's going to get hurt

I got Maggie a year ago from a shelter and they got her from a hoarder. I live in an apartment that doesn’t have a fence in the front yard and for the past few weeks Maggie has been running to the front yard, next to a very busy Street. She won’t come when called, obviously I want my baby safe
but, I also want her to be able and run around get exercise and have fun. The ‘backyard’ doesn’t have a fence either. The two yards are connected by a parking lot. Another problem is that there are trees around the ‘backyard’ and I got her a tether but I don’t want her to get tangled up with in the trees. Yes I will sit out there and watch her, but she is very quick. I thought about putting temporary fences up but I can’t leave them in the parking lot.