Hi
In Ondara with a 1.8m dish you may still loose BBC and ITVs late at night - maybe from 10/11pm at night, with BBC2 (Freesat Five, and the C4 horizontals) available until about 6pmish.
You will need the dish, LNB and groundstand (and possibly concrete base) - prices on the CB are around 700 - maybe you got the most expensive quote....
Personally, out of the new "flow box design" I prefer the Thomson over the Amstrad, as I find the Thomson performs much better especially in the Northern CB area, especially later at night and for those tricky North beam signal channels. But if you have a sky subsciption best go for a Pace
Sky+ box, better performance and all the benefits of the record and playback features.
I dare say the reason why you cannot get a lock on the Amstrad is down to the fact that
a) your current sized dish cannot receive the North Beam 11778 frequency (that is used for the signal strength lock indicator), (which is poor in the mid afternoon period anyway)
b) your LNB is not correctly aligned / skewed - critical for the North beams signals.
C) or your Amstrad is poor.
I am in Gandia just up the road and have managed to get a lock with the Thomsons on an 80cm dish, at least in the mornings til noon...
Hope this helps