I don't think his problem is that he can't pay - he's even offered to pay himself for state security.
RAVEC have said that he did not in fact 'offer to pay'.
His problem is that in the UK - unlike the US and most of the countries he has visited - private security is not permitted to carry firearms. Only state security can carry firearms.
No, I don't think that's his problem. Yes, his American security can carry guns, but only on the same terms as any citizen in California. They don't have any special privileges, nor do they have access to intelligence, which Harry claims is necessary because he's so terribly important.
Harry's problem is a) he's tight fisted and doesn't want to pay and b) he can't accept that he is no longer a senior royal and does not play any role in the life of the nation. But he's going to have to get used to it.
. Perhaps RAVEC should call his bluff and give him extra security cover now he's in the UK.
Ravec should provide security if, and only if, the intelligence warrants it. Not as some sort of game. We're talking millions of pounds of taxpayer money here.