Soil replacement for lawn

I’d get a quote from at least two other contractors and cross examine their capabilities! A good contractor will often provide details of other jobs successfully completed for other clients and seek their permission for you to speak to them or examine the completed work. I used two such contractors for the laying of paving and a driveway when I moved here over 10 years ago. Good contractors know that they will get referrals to neighbours, family and friends which often happens here. We also broadcast which contractors to avoid .

 

If you can't beat them, join them !
for 'Groundsweek'
GMA Home

 

It still sounds like you are going to end up with a very sandy soil even after adding that new soil.
Surely its going to be better to be on the side of caution and use a less sandy mix, so that it can be easily improved if needed.

After all, many lawns like ours are made just with a topping of typical garden soil over clay which as looked good for many years.

Would think its going to be easier to remove almost all of the existing sand and replace it with the grade of soil you want, which would think is about 20+ jumbo bags ?
Rotavating the existing sand into the new soil will be a job and equally risk damaging your drainage system.

 

@Dave King
I have found time to provide you with a written explanation of my previous tic post.
Soil Organic Matter is Good