Are there any mandatory technology requirements? E.g. for example, can the BPM solution be nodejs based? Does it have to be Java or .NET based? Can the solution be based on mongodb database engine, or does it need to be relational based, like MSSQL and MySQL.
What BPMS systems have you evaluated? What features did you like with those systems?
What is the total number of users? Can you breakdown by levels (Admin, Workflow, End User, etc...)?
Are you looking for named user or concurrent user license model?
Are you looking for a lifetime license + yearly maintenance, or a yearly subscription model?
Where are all the users located? Active Directory? Or a different Identity Management Tool?
Do you need multiple language support? If so, what languages?
What type of email do you use? MS Exchange? Google? Other?
Are there any hard/mandatory requirements regarding vendor and/or product certifications and standards compliance? Eg. ISO9000/14000/27000, ADA, HIPAA, etc.
Is there any hard/mandatory requirement for Process Simulation and/or performance prediction?
Do you require, in addition to BPMN, other business process related standards like BPEL, SBVR, or any other?
Do you require ad-hoc workflows?
Do you require process versioning?
Do you require integrating with any external system?