Thank you for submitting your item for appraisal. This appears to be a late 20th century watercolour, depicting a small harbour at the british coastline. Unfortunately this talented artist has left no imprint on the auction market. A number of other artist with the name Tinsdale or Tynsdale are known, but those work in a different style. The estimate is based on similar late 20th century watercolors by lesser known artists offered or sold.