Wow, I didn't expect so many generous advice. Thanks all! Only wish I discovered BP sooner.
@Joe Splitrock appreciate for bringing a different view to the discussion. I need to hear that too.
Unfortunately we will have to pay capital gain tax if we sell since we did not live there for the past 5 years. I might be exaggerating living 20 years in the new house, but def at least 10 years until after both kids are in college, not saying if it would make a difference. I too think in the long-run house would come out on top, at least equal, thru equity.
A common argument against rent, so was mine, where I'm also not totally convinced yet.
Assuming living in the rental for another 10 years with $5K rent/mth. That's $60,000 a year which equals to $600,000 in 10 years. The counter is that, while renting, we invest another rental by leveraging the paid-off-condo thru home equity loan, that would otherwise not be available if we sell, to generates more income to make up the rent. Hopefully we can make even, or even better, have additional cashflow after paying the rent. Plus, as @Stone Jin said, being renters are also liability free, considering paying for a service.
@Stone Jin may I ask does your rental increase over time? For mortgage, in the contrary, that monthly payment is always fixed.