[g_p]

There's also around 400 MHz of dedicated sharing-only spectrum in mobile bands, available in the UK at a flat price per 10 MHz required.

(Replying to GP)

At least in the UK, no bribes or envelopes of cash required. Nobody is going to want to help someone try to get started from scratch, but the spectrum access isn't anything like what you fear, at least in the UK. No connections required, the forms are all available online, and if you ask nicely and want bulk licences, you can use a spreadsheet instead for your requests, which is a bit less hassle than PDF forms.