So... Booking was done.
The process is quite simple.
Costs 350 Rs for 3hrs and additional 150Rs for each additional hr.
1. Select Accommodation-->Lounge
2. Enter day and time of check in,...
more... check-out
3. Check availability
4. Enter IRCTC log-in details
5. Enter passenger details
6. Pay
7. Get confirmation
No option for Wash & go ( Costs 175Rs more).. I hope it can be purchased at the time of check-in.
It is located on platform number 16., Ajmiri gate