SpaceX will only use brand new Dragon V2 craft for NASA crew missions.
Both SpaceX and Boeing were offered the option of reflying capsules
and Boeing plans to do so, landing on dry land on airbags and then
reflying each of their capsules up to 10 times. SpaceX, however, has
announced that they will only use new spacecraft for NASA crewed
missions (and still compete on costs because Falcon 9 is so much
cheaper than any ULA launcher).

So what happens with all the 'gently used' capsules that will be
stacking up at SpaceX? Apparently the plan is to switch them to cargo
versions and use them to fly ISS resupply missions under the next NASA
Commercial Cargo contract. This will let SpaceX do the cargo launches
for less than half the price of any competitors. Some number of Crew
Dragon could presumably also be used for non-NASA launches.


--
"The reasonable man adapts himself to the world; the unreasonable
man persists in trying to adapt the world to himself. Therefore,
all progress depends on the unreasonable man."
--George Bernard Shaw