Re: First Build Thread - BTR Inspired Cruiser
Very likely the wobble in the rear wheel is due to the bearings being too loose. You will need a cone nut wrench. Google it and see about adjusting the axle for wobble. It isn't a big deal fixing it, but won't get better on it's own. You don't need for a shop to do this. If it was an old Schwinn made in the US it would be 9/16". Yours is probably 15mm.
Someday when I grow up I will probably lose interest in toys with wheels, but until then...