Roots in pipes -no cleanout
So about a month ago, my toilet backed up and water backed up into my tub. It is an older home built in 1952, with no clean out installed. The plumber came out, took off the toilet and snaked the line with a small spear like head. He pulled out some roots, about the size of a baseball or softball when all waded up, and said we should be good to go for 6 months to a year. A month later, my toilet is leaking again at the bottom (no backup in the shower yet) and it appears roots have either grown back in, or something else is the issue. Also, we have a 4 inch cement pipe that comes out of the grown and connects to the gutter and runs to the sewer piping, and this has some wet toilet paper that has been pushed out of it too, which must mean things things are jammed up. I called the plumber again, and wanted them to run a camera through toilet opening, but they insisted on that we need a clean out installed, which of course is $2500 (2,200 if I dig the whole). Is there any alternative options that might save some $. Is installing a clean out easy to DIY? The piping is old cement like 4 inch piping I believe. My hope when calling the plumber would be that they would snake it again, and run a camera to see how big the problem is for a couple hundred bucks. I am going to call around for other plumbers, but any advice would be greatly appreciated! Thanks