Can you list and compare inventory discovery tools (used for L1) for cloud migration and cloud projects modernization?

Hi peers,

I work as a Senior Program Manager at a Tech Services company.

Currently, I'm researching inventory discovery tools that can be used for cloud migration. The only tool I'm aware of is RISC Networks CloudScape. 

I'm looking to get recommendations, shortlist and compare those tools based on the following criteria: 

• Security 
• Cost
• Depth of inventory (e.g., instance / database / services, etc.) 

Can you please share your recommendations and some comparison information?

I appreciate the help.