I would definitely opt for a service plan for this service. As said already it works out significantly cheaper than what you’ve been quoted as PAYG, and what would you do next year - a service B with additional items could be more than you think
If the last B-service was not performed correctly (items missed) would it be worth contacting the dealer you bought it from? It must have been approved used so I’d have expected these items to have been rectified prior to sale and for the warranty etc to be valid. Maybe approach them for the DSB to be sent to you and you can check what was/was not done (it would show this for the service in question)
Regarding the battery issue, if you’re only doing a couple of hundred miles a month, and short journeys, it’s almost certainly in need of a longer run and/or maintenance charge. A CTEK would be a great shout, especially at this time of year - and cheaper than a new battery which would likely end up with the same issue in a matter of weeks.
If the last B-service was not performed correctly (items missed) would it be worth contacting the dealer you bought it from? It must have been approved used so I’d have expected these items to have been rectified prior to sale and for the warranty etc to be valid. Maybe approach them for the DSB to be sent to you and you can check what was/was not done (it would show this for the service in question)
Regarding the battery issue, if you’re only doing a couple of hundred miles a month, and short journeys, it’s almost certainly in need of a longer run and/or maintenance charge. A CTEK would be a great shout, especially at this time of year - and cheaper than a new battery which would likely end up with the same issue in a matter of weeks.