it takes money to make money
One must start out with money to make more money, as by investing it in some way. I know it takes money to make money, but I work at a minimum-wage job—what am I supposed to do?
It takes money to make money.
Prov. In order to make money, you must first have some money to invest. I've been reading a lot of books about how to become wealthy, and they all make it depressingly clear that it takes money to make money.