If your gonna run Kodi (which is great btw) then have a look at openelec.
It is a stripped down Linux distro which runs great on the pi3. I have 3 of these running in the home in the various bedrooms and as has already been stated you can run them off old redundant phone chargers. If you pick them up from RS components they are dirt cheap ( do overclockers sell them?).
Amazon are selling them too.
The fire stick is another alternative as you can load Kodi onto that too.