The grass is always greener on the other side (of the fence)

red-letter day

silver-tongued

on the money

like a red rag to a bull

a bit (too) much

be (become) green with envy

zero tolerance

caught somebody red-handed

turn over a new leaf

have green fingers

spill the beans

zero hour

black and white

thing or two

be as busy as a bee

back to square one

a chain is no stronger than its weakest link

Money talks

a bolt from the blue