Implementing a CMDB [closed]

Depends on how much time and money you have to throw at it.

CMDBuild: Open source (Hosted on SourceForge)

Device42: DCIM/CMDB (Has some opensource software, no public pricing)

Solarwinds CMDB: $0.10/month per device + Agent Costs

iTop: Open Source (Has Paid Version, Community is mainly in Dutch)

Service Now is another option but is an Enterprise Software.

I'd recommend looking online for reviews of the product, websites like this provide some good information, but use them as a grain of salt as far as the best products.

If you are looking for a SaaS product I'd look at IT Glue (although I wouldn't call it a CMDB), I have first-hand knowledge of it. It's not a bad product, it works well and has loads of integrations with popular RMM software to gather device information and has documentation capabilities for documents/procedures and a password vault etc.