Always remember... when you evaluate a tree start at the base and work your way up.
(1) The surface roots and base of the trunk
(2) The trunk line, movement and taper
(3) Primary branching, location and scale
(4) Secondary branching and refinement
They are listed in order of impact on the viewer... and time to develop and fix. People will pay $$$ for a bare trunk with no branching if it has great surface roots and trunk line.
I consider your purchase advanced material

Not saying you can't make a great bonsai from it, but it ain't gonna be easy