If it’s just an oil and filter change or brake pads, buy the items and any even vaguely competent bike service place can do it.
This place for example:
Beto Bikes.
It would mean a journey over the Thames from Kent, but there’s a great ‘pop-up’ tea / brunch hut thing next door and the Tower of London / Tower Bridge to gawp in wonder at, both not far away. Waitrose and a barber’s shop, too. Quite a day out, really.
Maybe the OP could narrow down which tasks are beyond him, outside his pay grade and / or the abilities of the local Brownies?