It is a quite complicated question to give an answer too because many variables can affect the parameters you should look at : you will be looking for some if you want to develop the domain ,some other if you are going to use it for a PBN and different ones of you want to park it or sell it etc
Some domainers are all about the age forgetting that if name is a crap it can be centuries old but it will still be a crap
Some others are all for PR but PR archive hasn't been refreshed in over 1 year
Alexa is a quite common parameter together with Domain Authority and Page Authority.
More sophisticated and trustworthy are Trust Flow and Conversion Flow.
If you want to know the " basic " parameters then for EMDs you will look at the exact searches, cost per click, extensions taken , developed websites.
For brandables it's different again.