In my opinion, there are a few important things you can do upon purchasing new shoes that will increase their lifespan greatly. These include:
*installing thin rubber protective soles on leather soles
*immediately replacing the plastic top lifts (the very bottom of the heel) with non-slip rubber heels.
*spraying them with a water/stain repellent spray (this is especially important with light-colored suede and leather)
*buying a pair of cedar shoe tree to insert in shoes after wearing
All of the above can be done at any full service shoe repair facility.