If you’ve ever had a couch, odds are you’ve had a friend crash on it, or have been the crasher yourself. As strong as your friendship may be, it can still get awkward when the days spent on the couch lengthen and the question of money arises. So how do you navigate those tricky waters?

Forbes did a bit of digging, questioning and math, which we’re grateful for because some of us here hate math, and came up with some data to help figure out when to ask your pal to chip for rent, and how much to ask for.

Using author Jon Bittner’s site Splitwise.com, readers were surveyed on what people expect as guests and hosts, assuming the crasher would be on a couch or somewhere with less privacy than a guest room.

A few key points:
• Staying for a couple of nights is just being nice. Around 75% of those polled thought a guest should offer to pay after a week. To be a good guest, offer some payment or a gift or other deal around that time.

• As for how much, respondents didn’t really agree. A good tip is guests who stay longer than a week should chip in two-thirds of the rent for each night they stay. Since they don’t have private space, but also aren’t out on the streets, that seems to be a good deal.

• Another option is to ask guests to pay for part of the montlhy bills for the nights they stayed, which could come out to a lot less than the two-thirds rule.

For more of the stats and math stuff, check out the full article at Forbes.com.

How Much to Charge a Couch-Crasher [Forbes]

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