A whole few days?
Sorry Steve, don't mean to sound facetious but that's hardly a test of an antenna or prevailing radio conditions. With the radio interest it's usually about the long haul.
We had a dead spot in the radio spectrum for a couple of days over the end of last week/weekend due to a solar event but it bounced back lively as anything and there's even a bit of action going on the free-band frequencies right now. (Surrounding 27.555MHz as of 29/03/23 17:20 hrs) Great stuff for the DX interest.
(Check out the countries people got on the Charlie Tango 11m Challenge :- https://charlietangodxgroup.forumotion.com/t4727-11m-winter-challenge
. Inspirational stuff right there.)
If you mean local 'chat' either on the UK band or even CEPT Euro frequencies then that might be a bit more lacklustre depending on activity in your area. In some areas CB is thriving but in others too many shout out for a few days reinvigorated by the likes of 'Fred-In-The-Shed' and then give it up as quick as they took it up unfortunately.
As for being in a 'dip' you're not actually much different from my own location in Bedfordshire and I pick up radio chatter no problem even with my 'lawnmower lead' antenna in my loft.
Durham topographic map :-
The summer is when the skip really comes rolling in and we're ramping up a solar cycle so it should be pretty good if last summer was anything to go by. Might be worth waiting for those events before giving it up totally. Also worth shouting out regularly on a set of frequencies (Channel 19, UK & Euro as well as free-band frequencies) as quite often people listen for radio chatter but if everyone is 'listening' it seems like no one is there!
I wish you well with your mobile aspirations because at least you can get to high ground and maybe even closer to where there is some CB action.
Most things nowadays tend to be 'on-demand' with an instant gratification sense of satisfaction but radio doesn't really work out that way. Even on Ham frequencies you're at the virtue of propagation conditions or Mother Nature and she can be a fickle bitch at times. FT8/FT4 digital modes tend to fill in that void. (Seems you can make a contact with those modes at any time...something I enjoy myself.)
As for spending a few quid it's the same for any hobby interest really.
Don't feel too despondent, (easier said than done I know), and see how you go. Your mobile radio ventures may bear fruit and you'll soon feel reinvigorated again.
It's not 19-clickety-click anymore where you could pick up a mic and shout "19 for a Roger" at almost any time and be guaranteed an answer unfortunately. We also don't have too many of the "Bedroom DJ's" or the "bucket-mouth" brigade that used to hang out on CB either thank God!
If all the operators who we've handed out call signs to over the years were on air right now I'm sure the airwaves would be bristling with activity.
All the best,