nkk, other midwives are (or were, anyway) lots cheaper than CF. I think it was a difference of 30% or so.
And yeah, when you book with a single midwife, you only have her. But whenever my midwife was away or busy, she had other midwives (friends of hers) on call. I met a few of them, by chance, and they were all lovely.
She never booked too many patients in a month, and never took a holiday when any of her patients were due to pop, or nearly due.
I think she had missed a grand total of two of her clients' births. Both third babies, both just really really fast. She showed up to deliver the placenta.
So yeah, if finances are an issue, I'd look to someone other than CF. (Or a doula, as a much cheaper alternative. That still gives you someone who knows about birth and knows you, who's there to fight in your corner and/or give you support.)