Have problem with pipes coming from my toilet into sewrage , after having a blockage a company came out and cleaned the drain with pressure washer then he too a photo of inside the pipes to see why it keeps blocking and they found that 2 pipes that join one has slipped and covering part of the other one so instead of having a 4 inch for toilet water its now only 2 inches so the dropped pipe needs lifting.. how difficult will this be its about 18 inches under soil

Your description is a bit vague but digging up a sewer darin outside and relaying the drain can runseveral thousand dollars. Didn't he give you a bid? I would have at least two other plumbers run their cameras down there and give you a bid before you go any further

Its about 2 meters of pipe horizontal running to drain... he told us we can do it ourselves .my adult sons will dig down to pipe as its in my back garden and line the 2 pipes up and pack it up with a bit of cement...

Sewer drains are not set with cement so try to do some home work on the subject before your son attempts a repair. Do you know what material this pipe is made with? It would be your lucky day if all you had to do was raise it back in position. They usually are cut out and replaced with new material.

Its what I would call china , the photo is clear and is no more than a 12 to 18 inches down if that ,it's a 4inch pipe.. iv not a price for it as he told me it's a job we can do ourselves just by lifting 2 inches back into place

Clay tile, maybe? If so, its not going to be easy to just lift it up, as it is as ridgid as pipe gets, just won't bend or give at the joints. Dig it up and see what you can do. However, keep in mind that if you do more damage, you may be in a real mess. Keep a plumber on speeddial when you start the project.

Thanks for your help and suggestions. We will ease it very gently back into place and pack it up under neath with cement or soil depending what we find when we see the pipe... I think it may be clay.. its like china and orangey in colour .