Hi, my garden is about 8m square or thereabouts, with a left to right
slope, 1/3rd of which is below the floor level of the house. I plan to
digg out (the middle part) of the left of the garden and use some of it
to fill in the right side, after building a small retaining wall (so I
still have side access to my garage.)

I started doing it by hand and the top spade depth's is pretty easy but
under that is thick clay with egg sized stones in which makes work very
hard indeed. I was planning on digging down deeper than I needed &
then back filling with the top soil I had removed earlier. It seems
that a mini-digger would make this work much much easier. Has anyone
had any experience of using them?

The other question to ask is I was thinking of removing turves of grass
then putting them back later but from looking at what I've removed so
far I would have a very uneven lawn as my turves are only about twice
the size of a spade and not very even in depth (the sods.) The lawn is
also about 30% moss. Would it be foolish to forget the grass that's
there and attempt to sow a new lawn from seed after I'd levelled
everything out?

Thanks for your help!