We almost NEVER argue about money, and here's why.
We have all of our money go into one checking account, and if either of us wants to spend over $50 on anything, we have to discuss it together. So, my expensive shoes or handbags, a new coat for the kids, my hubby's hockey sticks...all over $50. We discuss the affordability, neccessity and desire for the item, etc. That way, we as a couple decide together and are in agreement either for or against the purchase.
Some items up for question raise more of a discussion than others, but it's BOTH or our money, even before it goes to the bank, and we BOTH get to decide what WE buy. Some conversations are a simple phone call. "Hey honey, i'm at macy's and there's this handbag I really want and it's on sale for $60. Do you mind if I splurge?" And we talk about bills coming up, expenditures, etc...and decide together. For me, I do most of the bills, so it's easier for me to know when I can afford something or not, so I just have to make the courtesy call for appearances, but I know most times, he'll agree...even if I'm buying yet ANOTHER handbag. Sometimes, having this rule forses me to really consider what I'm purchasing and in alot of cases, putting it back on the shelf.
We figure, $50 is alot...and if both of us spend $50 in one day, that can add up fast. All the rest of our money is community property and bills, etc get paid first, end of story! This is what we do, and it's worked for 10 years. :)