I've said this before- quoting Republic's website on how much the Royal Family costs the taxpayer is pointless. I mean, it's not like they've got an agenda or anything.
What organisations like Republic fail to acknowledge is that, even without the Monarchy, we'd still have a head of state. The head of state would require a residence and security. They would have a family who would also require security. There would still be state events. Through analogy with other republics we could anticipate that former heads of states would continue to have security once their term in office was over and might have some kind of state funded pension, which is likely to be substantial.
All of this would be paid for by the taxpayer. Its unlikely, however, that any elected head of state would be able to make the same contribution to the cost that the Royal Family do through their land holdings. Its also unlikely that the state events would attract the same level of interest without the Royal Family and so the economic boosts that such events provide would be lost (conservative estimates suggest that the money generated by the Platinum Jubilee was many times more than the cost to the tax payer of staging it).
On top of all that, we would lose all of the diplomatic leverage that having the world's most recognised and respected Royal Family gives. And we would lose all of the historical significance of the events, places, and traditions surrounding the Royal family which are an integral part of the national identity- which I think is more valuable than mere money.
