Dear client 

1. If defaulter pays the money within 15 days your sale will be reverted as bank has already informed you about this. And they will return your money.
2. If defaulter approaches the High court. There will be very chance if reversal of sale as the bank put the property on sale after the period of appeal expires. In case due to some genuine reason appeal got admitted and allowed bank will have to return your money immediately.
3. After the sale certificate is issued and registered the sale cannot be reverted without the interference of court. For that also time limitations matter and bank took any step after the limitation period expires. 
4. When the 100% money is paid and property is registered in your name the sale stands complete.
5. delay can only be due to some clerical work otherwise it won't take much time. 
6. Yes the auctions of bank are genuine and you can participate in these auctions. 

You can work out a settlement with bank court will not interfere.  In such cases there is a very less scope that court will reverse the order.  If 100 percent payment is done you can go for staying the same. 

1) your refund of 25 per cent would not be paid immediately but may take some time 

2) chances of reversion of sale by HC are bleak 

3) in case of reversion you would get your refund after sine time 

4) after issue of sale certificate chances of sale being reversed  are bleak 

5) if the defaulter makes payment Tribunal may set set aside the sale 

1. defaulter has to pay by 15th evening. If he does not, the auction will be conducted

2.where is this 15 days coming from? if the auction sale is reversed obviously bank has to refund your money

3. no. the defaulter than has to file a suit

4. on registration of sale certificate and handover of possession

5. yes, in case there is order from DRT. However you will be at liberty to move DRT for necessary reliefs. You cannot be made to wait endlessly

6. auction is conditional on the defaulter paying 50% dues by today evening. If he does not then auction will be conducted. Purchaser is not remediless as he can always apply to DRT for appropriate reliefs. So you can participate. 

Court has given time to defaulter, if he complied, His title is safe, and recovery from bank, sluggish.

Bank never pays immediately, bank will auction the property and collect the sale consideration and your money will stuck.

Till matter is subjudice before DRT, your title remain under shadow.

Question5 -- Very possibility. as bank auction the property on as in where in basis, bank don`t owns liability once property sold. 

No till Issue not resolve in DRT, might DRT stay auction on next date or annulled the auction. .