let me tell you

buy to let

To purchase a property as in investment, and to let it out for rental instead of living in it

don't let the door hit you on the way out

Used as a command to leave in haste, or to indicate that one is glad, or at least unmoved, to see the addressed person leaving.

don't tell me

Used to introduce a guess at a fact or situation, as if forestalling the other speaker's utterance.

I can tell you

Emphasises the truth of a statement.

I tell a lie

I am mistaken; I thought that what I said (or wrote) was true, but I have just realised that it is not.

I tell you

Synonym of I can tell you.

I'll tell you

Synonym of I can tell you.

kiss and tell

To betray a confidence by disclosing private information, especially of a sexual nature.