Back office processes in a schengen visa application [closed]

I'm an Indian national and have been to the Schengen area many times before. However, For the sake of information I would like to know how the process occurs once the visa application has been submitted to the consulate / embassy.

1. Do they call and check with the hotel ?
2. The embassy asks for the complete travel itinerary with booking confirmations. Do they use the booking code to check the airline website if the booking actually exists ?
3. Generally Is there a single person who looks at a visa application ? or does their visa approval process involve going through multiple people always ?
4. How much time do they spend per application on an average ?
5. Do they do a credit check with credit check agencies (like CIBIL, experian) to see the individual's liability and credit score ?
6. What other backend processes are involved in the life cycle of a visa application ?
7. What is the qualification of a person who reviews a visa application ? Bank statements and income tax returns are also submitted by me - so are they qualified enough to understand balance sheets, capital accounts summary etc. ? Or is there a process where an application is run through a financial eligibility check (with an accountant maybe ?)
8. Do they go through past schengen itineraries to check for overstays (by comparing with stamps in passport) or they have this information already calculated by entry / exit scans ?

I understand the above steps can differ based on individual applications and additional checks can take place however, I would like to know if any of these steps are a part of the basic process itself (undertaken for every visa application) and more if any.