Tom Anderson wrote:

The driver told them that he was not insured to take more than one
person, and that the price would therefore be 80 pounds for the two
of them. My housemate asked him to check this with his controller,
and after radioing in, he claimed that it would actually only be 10
pounds extra, at 50 pounds.

In the end, the colleague was so annoyed by this that she took the
tube. My housemate still took the taxi.

"minicab".

Is there any possible truth to his assertion about insurance,

While it's probably possible to license a two-seater car as a minicab, which
would then be only insured to carry one passenger, this is unlikely to be
the case here. It's certainly not possible that paying extra money would
solve any problem.

or was this a barefaced attempt at a scam?

Barefaced attempt at a scam. Similar things frequently happen going towards
the airport, when the minicabs rely on people not wanting to miss their
flight, having no time to make alternative arrangements and leaving the
country. The foreigners ask the hotel for a "taxi" for four people - they
are told it will be 50 quid - they say fine, because the black cab they took
from the airport cost 60 quid - when it shows up it's 50 quid per person -
40 quid ends up going into the pocket of the hotel concierge. I have no idea
why this is legal when it is not legal for taxi drivers to behave like
this - the assumption that market forces will keep minicab companies in
check clearly does not work in this sort of situation.

Out of interest, any idea how much a black cab from Heathrow to
Finsbury Park would cost?

70-75 pounds at that time of night, less during the day. Taximeters work on
the assumption that the driver will have to return empty, which in the
provinces and suburbs is nearly always true. The minicab company will
usually tie up a trip to the airport with a trip back from the airport, and
will be using a cheaper vehicle and so should be charging around half the
metered fare. Suburb to suburb minicab trips usually cost a similar amount
to the metered taxi fare, because the opportunity to also get paid for the
return journey is not there - but can easily cost two or three times as much
as a black cab if they "see you coming".

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