My testfor scoreboard command is not working

The issue is that

/testfor @p {score_money_min:5} 

doesn't work because of two reasons. Firstly you have to use square brackets and join the selector and data tag. Like so:

/testfor @p[score_money_min:5] 

then the last problem is that you have to use '=' in selectors and not ':'.

/testfor @p[score_money_min=5]

Hope I helped!