Changing a cambelt is one of those things that need doing like
changing the oil and filters. I'd put it a little above that very
basic service item level of difficulty because it's one of those
things that are easy once you know how but takes an hour or five the
first time.

See another thread for costs.

If you are really happy with your present car I'd stick with it, you
never know what you might get with the replacement.

Can't help on the costs etc. but, having had two 405's and a 406, the
difference is not that great, other than the 406 boot being smaller and the
fuel tank bigger.   Obviously there are extras that weren't around/available
in 405 time but as far as driving and riding is concerned I'd say stick with
the one you've got.

When I had my 405 the belt cost about £35 with labour another £25 that was a
few years ago
Last year to 18 months ago my 406 V6 belt was £56  with lablour about
another£40 -50 In the end it shouldn't break the bank

Hi Bob
put a belt and tensioned on it, also change the water pump while your in
there , and it should give you another 60k,
but if your in the market for an upgrade, sell me your 405, we need another
in our family
email me if your interested,
Fitzy

Belt's around £20. You could ask Peugeot as a guide because it is a book
item -- was quoted about £120 by Peugeot Liskeard last summer, so I
reckon Bristol would be a bit more. In London it would have been well
over £200.  In the end it was done by a non-Peugeot garage for £60 all
up. But it needs someone who knows about the tensioner, and as mentioned
... consider getting other things done at the same time. Certainly with
your mileage I'd keep the car -- but that belt if original is old and
needs changing even if it hasn't done the full 72K.