Roughly how much would it cost to replace my patio, wall and steps?

I have a flagged patio of about 6 sqm which is supported by a 10 ft brick wall. There is also about 8 flagged steps leading down to the garden and all of this needs replacing as the wall has no foundations so is slowly subsiding and taking the patio and steps with it.

I have already checked with my home insurance but I am not covered for this because it isn't affecting the house so I am going to have to pay for it myself.

Can anybody advise roughly how much it would be?

Sorry to hear about this. I am guessing you have flagstone, which is rough cut field stones laid in mortar or concrete, stairs and patio and then below it supporting it is a ten foot drop off or ten foot legnth of a retaining wall that supports it. If you going to replace all of it then you may want to call in a landscape architect, to redraw the shape and size to best suit your yard, if you just want to repair it maybe you can get a handyman or independent landscape contractor to bid it for you. Try to find a sample of the material you want to use for the new patio, such as flagstone, or paver tiles, or whatever, at least a picture, so they can bid it for you. If its flagstone Id try to have it repaired first.
Maybe they can extend the borders of the patio and build new reinforcing around that?

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