Advice on trying to get builder to rectify poor garden

Folks, apologies for the long post.
Moved into a new build estate circa 16 months ago.
Back garden had grass seed thrown on top of what looked like poor soil due to number of decent sized rocks that were visible including the odd piece of litter appearing out of the soil!!

When speaking to foreman about garden and its poor growth he would say give it a year and stick a fork into the soil. I did all that and joined here and got very helpful advice.
Following advice on here and advice from a professional I had out, the following is everything I did at some stage or multiple times
1. Aerate regularly
2. Added sand to improve drainage
3. Raked the moss/thatch out
4. Added fertilizer
5. Added lawn feed
6. Added grass seed
7. Religiously got down on my hands and knees and took out weeds, creeping buttercup & clover. I now have couch grass in my garden following identification through a post on here.

Aside from all the above, most of the soil has moss sitting on top, there are patches where it is just moss in the garden, there is a part in the middle of the garden where it pools rainwater days after it rains, I have unearthed large stones beneath the surface as I aerated the lawn, there are a couple of patches where grass won’t grow and the area around the back of my garden is constantly wet as their is a neighbouring estate on an incline whose back garden would face onto and down into our back garden so their garden likely drains into ours.

From all the advice on here, it is clear the soil is poor, it is badly compacted, poor draining and the best advice would be to start it all over from scratch. Remove everything, bring in proper sand, topsoil and plant seed again.

It turns out a few neighbouring gardens complained to the builder and had their garden taken up and replaced with new soil and rolls of turf.

Builder came out two months ago to view garden and took pictures. Then they went dead silent and I have chased them non stop for an update since. Eventually they got back to me to say they will send someone else out to review it as the last person to review it has left the company but he said my garden was fine - which is hard to fathom when there was a pool of water in the middle of it even though it hadn’t rained in days.

The fact they replaced some neighbours gardens who according to them mine is in worse state and are practically refusing to replace mine has me extra determined especially as I put a lot of work in to improve it and it is a losing battle. Also, I briefly spoke with a legal professional who said I could have a case for a breach of contract as the house I bought based on what I was told and seen in the show house is not what I was delivered, it would mean going down the small claims court route.

The grass has not been cut for a few weeks now but I think if they come to inspect the longer grass may hide some of the issues. Is it worth my while cutting the grass to show the poor growth, the moss on the soil, show the damp soil and pools of water but cutting the grass will make the couch grass less transparent ?

 

The soggy state and moss are apparent even in the pictures, so an inspector should be able to see them @NoviceGardener2023 . It doesn't look that long, so I shouldn't worry about cutting. Unfortunately anyone coming to inspect at this time of year might say "it's normal" due to winter rain - even though you know it's always like that.

 

I just get the feeling that in many cases you can't do much on your own.
The drainage on some of the new build sites needs sorting out as a whole, its a losing battle, imo, just trying to improve one patch, and the builders probably know it.
I don't think garden drainage is ever taken into account when they build houses, let's face it they build houses these days in areas that even likely to flood, so I doubt any thinking goes into the suitability of the garden.

 

At least part of the problem is going to be down to ground being compacted by heavy machinery during construction. That will require more than sticking a fork into the ground to resolve.

 

Apologies, I should have been clearer in my post, those pictures are from around 6 weeks ago, the grass is longer now so ai may cut it to make the state of the ground clearer.
Yes, I suspect the fact they are now coming out nearly two months later they will say this is typical soil conditions for this time of the year. The attached pictures were in September.
If I was to get an independent expert to come out and assess the garden state(with the intention of using for any small claims court case) would a professional like a gardener/landscaper be professional enough or would I need some sort of gardening engineer, if they even exist. As it ultimately comes back to the soil and how it was prepared etc. maybe an experienced gardener is enough.

Garden is south/southwest facing so most of the garden gets the sun at some stage. A part doesn’t get too much of it typically until evening time and that area is particularly wet but also happens to be the end of the garden.

 

It would be good to see a picture of your whole garden and in relation to your neighbours so we can see how the water may run in or be controlled.

Possibly the reason they may be avoiding your garden is they may know yours has a lot of waste under the top soil, eg typical of the last house/garden to be built on that row or site, or that to get machinery into your garden would be difficult due to buildings and/or very soft ground etc.

Have you dug one or to test holes around the garden to see whats under the grass ? eg typically down 40- 60 cm.

 

Maybe forget about grass entirely and make a rockery/gravel garden.