The absolute standard of the recipro-saw world is the Milwaukeee Super SawzAll.
On sale at some our local discount places, it is about $180. Logical question
is "why pay that much?" Logical answer, "try it out, see the difference". The
Super has a unique antikickback action that means you can use it with one hand
atop a 24 foot ladder. It is similar in effect to the difference between a
straight shotgun and a recoil-operating piece. If all you ever do are crude
cuts, than save the money and buy something else (even beer). But if doing a
consistently tidy job is important to you, the Super SawzAll is the way to go.