1031 exchange requirements

[Ki Lee]

When doing a 1031 exchange, does the newly purchased property have to be equal or greater value than the sold property?  

Or is it that just the profit from the first property must be all invested in acquiring the next investment property?

Example- let’s say that Joe sells a property for $650k. Joe still owed the bank $300K at the time of the sale,  so he gets paid $350k.

Now will joe have to buy a new property that is at least $350k(his profit) or $650k(value of the sold property) in order to satisfy the 1031 exchange?