Scottish sasine records are records of land transfer and ownership, and are particularly valuable where ancestors owned land, however small. But in many cases, particularly at a local level, they are unindexed, and voluminous to search, so essentially out of reach, unless you can spend a long time in archives in Edinburgh, or pay someone to search the records.
Very kindly Graham Maxwell spotted a couple of Cavers references during other research he was doing in local sasine records for Roxburghshire, and forwarded on images of the relevant documents to me. They concern a father and daughter: John Cavers, merchant in Hawick, and his daughter Isobell.
The first reference dates from 1739, when John Cavers merchant in Hawick seems to have been owed 14 pounds Sterling as an annualrent regarding a tenement of houses within the town of Hawick. Then in 1756 Isobell Cavers spouse to John Currer Skinner in Hawick had sasine of a tenement of houses in Hawick, presumably the same one, which she inherited as daughter of deceased John Cavers merchant there.
There’s no marriage that I could find recorded in the parish registers for Isobell Cavers and John Currer, but they had three children baptised at Hawick: Thomas, in 1742; Mary, in 1743; and Margaret, in 1745. Going back in time I suspect that Isobell may have been the daughter of that name christened at Hawick in 1720, with parents John Cavers and Marion Newbie. Certainly a mother called Marion would fit with Isobell naming her own daughter Mary, a variant of that. The Hawick parish registers in the early 18th century are detailed, including occupations for fathers. At this 1720 baptism the father was noted as John Cavers merchant in Hawick, which definitely fits with the sasine family. On the downside there are other children recorded for John and Marion Cavers, but perhaps they died young.
Hopefully more early Cavers sasine references will come to light, as the records hopefully become easier to access.