Cenvat credit

Dear Experts,

                   My query is regarding cenvat credit available to a bank. We being a bank use input service of computer AMC and annual subscripttion of software. 

Question -1 Can we avail 100% cenvat of both of these services? If answer is no, please tell how much cenvat credit we can take?

Question-2- We pay service tax under rcm on advocate's fee, how much cenvat we can avail on it?

Question-3- We pay 75% of service tax under rcm on detective service/manpower supply of security guards. How much cenvat we can avail? Please guide.