1982 Tercel

I have a 1982 Toyota Tercel bought in Yorkton Sask. in 1984 with 15,000 km on it. In 1986 I had it shipped to Yellowknife where I drive it very little, and in the last few years, not at all in the winter. I don't plug it in the winter and it starts in the spring year after year. It has very little rust as no salt is used here as too cold.  I am trying to set a value for sale and would appreciate any advice thanks.