I was hesitant to build my little trailer set up using a couple 55 gallon drums but it sure makes for less trips and has worked well but cost more than I thought it would. If you make a business out of it there are permits/license and insurance/bonds that are required that means at $45 your probably averaging $25 or $30 an hour and praying the knife valve works and the hose don’t come off! You need a way to haul portable water as well as a blue boy neither of which is cheap. I usually dump/fill once every 10 days so $135 a month, yeah the little trailer is looking better all the time. You guys should consider getting a group together to make a community trailer since you do extended stays. If you do and need help building one or a place to store it let me know, I can maybe help out.