We’ve had cover via a Nationwide Flex account, but have now moved to the Co-op as their penalty free upper age limit for travel insurance is 80. Nationwide was 70.
The fee is £15 per month, which includes travel and mobile phone insurance, and RAC breakdown cover. This would be the same for a sole or joint account.
We pay an additional £70 per year for my husband’s fairly serious existing conditions.
The travel insurance allows multiple trips per year providing none is longer than a month (I think. It may be 28 days), and I believe the RAC element is limited to three call-outs per year.