Depends on where you go, you may get ripped off. Adjustment is
easy if you can get under the car. Brake shoes vary a lot in
quality, I abandoned OEM Fiat, in favour of branded such as
Raybestos, although there are other quality premium brands.
Everybody swears by their personal preference, and rubbishes
the other brands.
Garages tend to buy the cheapest, often unbranded, and
of poor quality, because they get the best profit margin.
For such a safety critical component it's worth the bit extra
for branded quality items.
I'd query what brand they fit, and cough if it was much
over £100.00, wheel cylinders, which they might add on
(regardless of their condition) about 50 quid, both inclusive
of fitting and excluding VAT. It's basically the same as for
Mk1 and MkII Uno's.
Most of the cost is labour.
In pssing tyres and lamp bulbs have to meet stringent
Euro standards, AFAIK there are no such standards
for brake shoes, other than the MOT test.