For all somebody/it is worth
Definition 1 of 2
Pro Tip 1/3Humble Offering
Expresses modesty about the value of one's thoughts or possessions. 
Here's my two cents, for all it's worth.
Pro Tip 2/3Understated Value
The phrase might be used to introduce an opinion that the speaker thinks might not be taken seriously. 
I suggest taking the left turn, for all it’s worth.
Pro Tip 3/3Pessimistic Tone
Can convey a lack of confidence or a belief that the effort or input won’t change much. 
I'll vote, for all it's worth, but I don't expect much.