No Spending Challenge

Im considering doing a no spending challenge.

Or this one:

My question is: where do I draw the line? For example, i wouldn’t give up scuba diving for this. But I would eat meals from home and (try to) stop restaurant meals.

My objetive would be to stop spending money on trivial unnecessary items. For example, one of the dogs leashes broke this morning. I can either: A buy a new leash or: B: use an older leash that’s still good. Another example would be, not giving up nutritious food for the cheapest food available. But then again, where is the line?

Ive been thinking about this since I first heard about it. It seems pretty cool. What do you think?