(humorous) Being available for sexual relationships with various people is preferable to committing oneself to a single partner.

Alternative form of why buy a book when you can join a library

Alternative form of no matter how thin you slice it, it's still baloney

Alternative form of don't count your chickens before they're hatched

Alternative form of the fucking you get isn't worth the fucking you get

One doesn't require an expert to tell one what one already knows.

Alternative form of the fucking you get isn't worth the fucking you get

Synonym of you don't dip your pen in company ink

When finding oneself in a troubling situation, one should first make sure one is not making the situation worse by his own actions before addressing all other causes.

Do not expect somebody to make a costly commitment if it will give them nothing they do not already have; used especially as a warning against having sexual intercourse before marriage.