I recall some Karcher can have a failure mode around the pump
casing, it leaks, and is a design issue. So beware spending too
much assuming indestructable. That is many years back, and I
suspect that may have been limited to a particular model.

I would not use a pressure washer for a car.
o Pressure washers can remove decals, perhaps damage seals
---- they might also get under your wheel arch undercoating
o Steam cleaners are different beasts to pressure washers
---- main use is engine bays, then add dye to find leak sources

If you have tar etc:
o Use Zymol HD Cleanse - also good at removing oxidised paint
o Based mainly on various fruit oils, marked up accordingly

A Ferm pressure washer would be ok for doing paving 2x a year.
So if your usage is low I see no problem, although you can also
buy refurbished Karcher pressure washers - big ones £40-60.

Where Ferm is "usably" different to say a brand like Makita:
o Cordless drill
---- Makita has ultra low-speed yet good torque
---- Ferm is more a disposable garden shed / DIY assembly tool
o Pressure washer
---- it squirts water - opportunity for differentiation is less
---- top brands will last longer re duty cycle (like a big laser printer)
---- cheap brands may match your usage fine

Warranty is not indicative of life - you can do a design so cheap,
yet still price high enough that warranty issues are not a concern.

Part availability IS a difference between the power tool brands:
o Easy to get service on Hilti, Hitachi, Bosch, Makita, BDK/Dewalt etc
o Generic brands may have more difficult servicing arrangements

Might be worth checking the local power tool places, they often do
refurbished tools at "Ferm pricing", with a warranty & easy servicing.

Pressure washers are water squirters, you don't tend to drop them &
crack the casing half way through drilling a water pipe or mains cable.

Hozelock & others do brush/hose/shampoo combos, the shampoo is
good at stripping wax off and not much else. The brush is useful tho.
Doesn't trash painted woodwork, plants & such like a pressure washer.
--
Dorothy Bradbury