Don’t break the bank buying your boss or colleague a gift.

Mariah Carey may have spent $34,000 on a Louis Vuitton trunk for her manager Stella Bulochnikov, but etiquette experts say their working relationship is an exception to the rule.

“You want to be professional and mark the occasion, but you also don’t want to go overboard,” Monster.com career expert Vicki Salemi told Moneyish. “It can get really complicated really fast.”

And really expensive. What if the rest of Carey’s team expects to get five-figure designer bags? Now it looks like the diva is playing favorites.

“Your best bet is to do something thoughtful and inexpensive that can be shared, like signing a communal card, or ordering their favorite cupcakes or bagels for everyone – or smoothies if someone is watching their sugar intake,” Salemi said.

In fact, you’re probably not expected to give a supervisor or coworker a gift at all. But to play it safe – especially at a new job – ask colleagues what has been done for past birthdays.

“Typically a communal gift where everyone chips in for the boss can be a good idea,” Salemi said, suggesting a spa day or a donation to a favorite charity.

But keep it professional. “You don’t want to give a gift that’s too personal in a business relationship,” warned Daniel Post Senning, etiquette expert and great-great-grandson of Emily Post. “A nice pair of silk pajamas is something your spouse might love, but it may not be appropriate for a boss or coworker.”

Plus, you risk appearing to be a brown-noser by getting a very expensive gift for someone who outranks you. “You don’t want to look like you’re trying to bribe someone or curry favor,” Post Senning noted.

And bosses should also be careful of giving subordinates anything too fancy. “You don’t want to play favorites and create imbalance between people operating on the same level,” Post Senning said. Consider holding a team lunch meeting once a month where you toast recent birthdays.

If you do have a more personal relationship with a coworker or supervisor who is more like a mentor, however, it’s OK to get them something nice and thoughtful. Just keep it discreet.

And don’t discount “just” giving a card. It only costs a couple of bucks, but the sentiment behind it is priceless. “A card with a handwritten message shows a personal touch, and you can leave it on your desk as a reminder of that person and the thoughtfulness that is behind it,” said Salemi.

And if you’re friends with a colleague and want to do something more, get them something thoughtful to mark the occasion, like a lottery ticket or a book by their favorite author.

“It really is the relationship itself that should be your guide,” said Post Senning. “Think of who the other person is, what the connection between the two of you is, and what’s going to be appropriate to honor that relationship and brighten that other person’s day.”