sparing no money; regardless of expense
Fixed expression meaning to spend money lavishly without concern for cost. Often used with verbs like 作る, 集める, or 買う.
He spared no expense and bought a luxury car.
He is collecting art from around the world, regardless of expense.
From 金 (money) + に + 飽かして (the -te form of 飽かす, an old transitive verb meaning 'to use to the full' or 'to satisfy fully'). Literally 'using money to the full'.