Some people get a domain appraisal from automated software. Each domain has its uniquness and needs to be evaluated by an expert who has at least 10 years of experience.
To be an expert, you need to have at least 10 years with a heads-on experience in each stage of domain industry, such as domain appriasal, domain acqusition, domain selling, domain portfolio management.
*** Don't miss out that your opponent probably has getting a domain's real value with an expert report.