Looks good. But it needs a bit more detail. For example, the wall behind the safehouse could be made like an actual brick wall. Maybe make window ledges or flowers on some of the buildings. Add pools of blood, wrecks and flaming things to make it scary. And what's the point of all the vehicles? Nobody would have a stunt buggy in the middle of the street like that.
Also, for the exterior-only buildings make a locked door or something. Add bus stops, benches and stuff that is normally in a city. Also, traffic lights and signs. I believe there is a complete street sign pack somewhere...
If you need any suggestions ask people, most will be happy to give you some.
And is JO's autoshop misspelled intentionally?