Meaning: dependable source for value. Use examples.
Rewrite 1: a walking ATM
Rewrite 2: your own personal money machine
Rewrite 3: a domesticated2 drive-thru bank
Rewrite 4: the family cat made of rolledvt11 coins
Rewrite 5: a dog that eats scraps but craps cash

Comment: There are some interesting possibilities here for rewrites. Watch that last one – it might offend some.

More reading about clichés
What I found when I googled “clichés”:
• “25 Cinematic Clichés I Never Wanna See Again,” by Robin Bougie, The Cultural Gutter.