Looking at buying a portable black tank - suggestions?

Instead of a sewer tote, a buddy of mine made a bladder that he uses a macerator pump that he pumps the waste water up into it. I liked the idea so much that I copied it and had one made. I can offload about 100g of water at a time. It’s nice because we can shower and run the clothing washer/dryer like we have sewer hookups. Plus, I empty my friends rigs as well.

http://learntorv.com/sewer-bladder/