Yeah lots of variables to consider, many of which relate to when you bought.

Loan-to-Value (%Equity)
Are you paying PMI?
Are you itemizing deductions?
What is your total payment?
How much would it cost to rent your place now?
Will you have to move for any reason in the next 3 years?
What is the state of your career
What are your property taxes?
What is the pain/cost of moving?
Can you sell it without realtor fees?

I’m sure there’s more.

Be careful of the question you ask – The question isn’t – in 5 years, will they have made money on the house (i.e. sales price vs. purchase price). The question to ask is: In 5 years, will they be more ahead if they sell, rent, then buy or more ahead if they stay put?

It is a difficult, personal analysis and it involves the risk of not knowing how cold the market will get.