What would 1031 exchange look like in our scenario

[Ana Vhan]

We have an investement property, which we plan to sell and buy propertie/s in 1031 exchange. Have questions around those. Please help. 

Let's say we we bought the proporty for $600K, sell the property for $1M , say a morgage of $400K was pending at the time of selling, say $80K is closing cost, say we spend $50K for rennovation before selling. 

1. What would be the total reinvestement amount expected under 1031 exchange?

2. Does the new investment have to be a single property or can we invest in 2 new properties where the total value comes close to #1?

3. Since we have mortgage on the selling property,  are we required to get a morgage for new property as well or we can do all money down ?

4. If we are unable to reinvest all required amount for 1031 exchange, what portion of the gains get taxed ?

Thank you! As always appreciate your help.