very poor, broke, in the hole

poor as a church mouse

в потоке речи может использоваться выражение make both ends meet

- Let's ask Dave. Maybe he can spare four grand? / Давай спросим у Дейва. Может, он найдет четыре штуки?

- Are you kidding? Dave's borke. He's poor as a church mouse. (He barely makes both ends meet). / Ты шутишь? У Дейва нет денег. Он гол как сокол.