'Use a Brompton for daily commuting in all weather they wear really well.'

Not always:

Sometimes the frames crack

Or they rust through:

And the wheels wear:

Or the handlebars break:

Or the seatpost cracks.

Or the rear triangle snaps.

Gears break,

Tyres wear quickly and are prone to punctures

Pedals break and rims wear out.

Just like any other folding bike, really.

"was staggered by the prices. I'm preferring to stay in three figures."

Yup

There's plenty of choice.