I wouldn't want to DIY an excavation like that and would certainly not want to work in it. Just pay someone to design the solution and someone else to do the work. Might be expensive but should be factored in to the purchase price.
@Cupcakes started
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I wouldn't want to DIY an excavation like that and would certainly not want to work in it. Just pay someone to design the solution and someone else to do the work. Might be expensive but should be factored in to the purchase price.