9 across: How we pay less often after shop robber of yore (6, 4)
10 across: Rejecting famous Battersea? (4)
Not even a once over with Google helped with this one.
15 across: Again try — big edge nicked — appeal! (9)
I thought it might be appeal = tempt, big edge = tear, big edge nicked = reat, which gives big edge nicked — appeal! = reattempt = again try, but I’m unsure.
17 across: Bleak Dover captured retro spirit (5)
Retro spirit might be rum or ale backwards…
20 across: British trendoid called in resale on mobile (6, 6)
Might have something to do with mobile = ringer or mobile = ranger?
3 down: Brings up the rear? (6-6)
5 down: Registered a mariner strike (7)
13 down: Supplies for dreams? (10)
I can’t remember the last time I had less of a lead on a clue than for this one.
14 down: This sort of detective doesn’t run! (4-6)
8 down: Turkish delight minus six-pack? (5, 5)
We figured the answer was belly dance, just that we had no reason as to why.
1 across: Foot bone armoured at near end? (10)
No one could quite figure out a cogent reason for why the answer is metatarsal, but it does fit!