Thanks all who replied.
Cardiff was looking pricey with mandatory handling from Signature (that'll be at least £100 sir).
Swansea closed at 1730 LCL (!) and it would have cost £130 ph or so to stay open for me.
Upfield is too short for my ovation at 600m, I need minimum 800.
After much contemplation I used Miskin Manor in the R44 instead, didn't need ATC, didn't require fuel, security or fire cover.
Lovely people there charged me nothing for landing and parking.
SB