Dont read mixed reports.....
It is possible for extending a 30-day on arrival visa for Indians in Qatar to another 30days...as of today.

Is it possible to extend for another month?
Yes
Yes
Yes

Also what are the charges for the on-arrival visa to Qatar and how should one pay it?

Free
Free
Free

I will post a link to renew online for free....

You can tell me the Passport number.. I can do it for free...