no strings attached

hold the purse strings

To be in control of spending; to have financial power and responsibility.

loosen the apron strings

To allow greater freedom (to someone); to relax control of (someone).

loosen the purse strings

To increase spending or allow increased spending; to relax control of spending.

pull strings

To manipulate a situation, especially by asking favours of others; to use one's influence with others to attain a desired goal.

string attached

A condition, catch, limitation, caveat, restriction, or requirement

tighten the purse strings

To decrease spending or disallow increased spending; to increase control of spending.