In Finland, genealogy records are maintained by several different authorities. Where you order depends on which registry the person belonged to and during which period.
In most cases, documents are needed from multiple authorities. It is usually not enough to order only from "DVV" or "the parish".
Certificates are ordered from the Lutheran church for all periods when the deceased was a member. A single request to any EVL regional registry covers every Lutheran membership period the deceased had in Finland, regardless of how many times they moved. The Evangelical Lutheran Church of Finland has 14 regional registries.
DVV provides certificates for periods when the deceased was not a member of any religious community. DVV also maintains the population register for all Finnish residents from 1 October 1999 onwards.
If the deceased was a member of the Orthodox Church, certificates are ordered from its central registry. This is a separate organisation from EVL.
The National Archives holds very old records not available in electronic registries, as well as records from ceded territories such as Karelia. Processing usually takes around four weeks.
If the deceased or an heir lived in Sweden, certificates are also needed from there. From 1 July 1991 onwards, Skatteverket provides the certificate. Records from before that date are held by Riksarkivet.
In practice, this research is the most time-consuming part when doing it yourself. The registry history must be systematically reviewed and the correct order sent to the right authority.
Key principle: The chain of official certificates must be unbroken from the deceased's 15th birthday until date of death. If a certificate is missing for any period, for example because of a change of registry, the estate inventory cannot in practice be completed properly.