Growing lawn where paving used to be - do I have a problem?

Very well phrased there Shiney.
I was a landscape gardener for over 30 yrs before retiring last year . I would always give a price for each job ,listing all work to be undertaken ,if you saw that there was a possible problem area that may incur an extra cost this would be mentioned at the time .
If for some reason you did hit an 'unknown' and it was not major I would just take this onboard ..

An expensive price is not always an indication of a better job .
I came across lots of jobs done like Rocklandsboy and it certainly gives the trade a bad name .
Best getting a 2/3 quotes and ask around for names of well known reliable landscapers.
However all this does not help Rocklandsboy ..

Best thing is to use a spike and test where the concrete has ben left (I would suspect most is still there) Then turf would need lifting break out concrete , hire small breaker if needed ..infill with soil and relay turf .
Was nobody at home when landscaper was there ?

Dave