How much could I reasonably gross per month w/a 2-car hauler?

Hello all. During a recent 7 month hiatus from my accounting career, I began a small transport company using Uship as my main source of loads. I used a 5x8 open trailer and hauled mostly motorcycles. I pulled it with our Yukon, so I tried to get a shipment that fit in the back, also. If I was able to coordinate 2 motorcycles and a small piece of furniture both coming and going, I actually made money. I had no overhead to speak of...just the cost of fuel and repairs.

Though I am back working in accounting, I really enjoyed certain aspects of small hauling. So, I was thinking about moving up to car hauling. I have a CDL (Class B with air brakes and passenger), but I would rather keep the loads below the 26,000 lbs threshold. For those that are experienced in car hauling, how much could I expect to gross in revenue per month using a 2-car hauler? I realize a lot of factors play into that. I'm just looking for a reasonable range.

Also, is there a need (niche) for hauling just a couple of cars?

Thanks!