Keep the house or tear down?

[Sam Yeung]

hi everyone, first post here :)

my parents owns a very old house with a larget backyard at Shoreline WA, seeing the recent housing market boom, we are starting to think about how we can get the most value out from the land and move to somewhere less expensive to live. 

what we have now :

a 1950 house with unfinished basement (~1500sqft)

total lot size is 22000 sqft, zoning is R6. From my own research if I tear down the house I could subdivde into 3 lots.

questions :
- currently the house is sitting in the middle of the lot, if I dont tear down the house, I can subdivide 1 addtional lot, is it worth it to do tear down the house and get 3 lots?

- is there a way to find out how much a 7200sqft lot worth currently? kind of thinking to tear down the house/subdidved and sell all 3 lots on market