I will be in Johannesburg between July 19-22 and would love to know where to stay, best places to eat and what to do. I love adventure activities, I'm a female traveling alone, budget is pretty tight and i'm easy going, so open to any and all recommendations for hotels, activities and restaurants.
Tight budget means different things to different people ;)
Avoid the city centre in terms of hotels , restaurants , activities.
Joburg is a big place with not so strong public transport , so without a car it might be difficult to get around , depending on what activities you have in mind.
For activities try booking tours. That will take care of the transport issue and you will meet some people.