Which databases or lookup tools do you refer to for validating IP fraud scores?

We tend to not rely much on any such lookup tools as they do not correlate with the experience you would face on a particular website. Major websites have their own algorithms and mechanisms in place which may or may not include these lookup tools.

What really matters is whether the ISP Proxies delivered to you actually work for your specific use case or not. We suggest our clients not to rely too much on what a third-party lookup tool says. 

As it is with the residential / hosting classification of ISP Proxies, we cannot guarantee if the IP will have the same fraud score over time or if it will increase or decrease. These decisions are solely made by third-party algorithms which we have no control over.