When you’re researching a family who owned property, try making a list to see how they acquired it and where it went. Properties for which you can’t find a purchase record may have been inherited from an older generation. Tracing the ownership of the property can help you identify other family members.
This technique is one of the ways I was able to build a case to prove the parents of Griete Smit, as I wrote about in the National Genealogical Society Quarterly in December 2016.