A car probably costs around 50 cents a mile to operate including gas, insurance, wear and tear, etc.
So you'd have to figure that against what you make.
How much do uber drivers charge?
Real estate agents can make some good money but it is not easy to actually make money. You have to really work it and it takes a lot of time nights and weekends. The expenses can again kill any profit and there are substantial upfront costs including education classes.
Why not just get a part-time hourly job for $8-$10 an hour and work 10 to 20 extra hours a week? You check in and check out and no after work worries. Like a Home Depot job. Work an extra 40 hours a month and bring home $300.