* keeps vehicle cleaner...less washing needed, less paint scratching potential
* from sun - paint fade, interior seat and dashboard cracking from heat and UV, yellowing of polycarbonate headlights; cooler to get into in summer
* from rain - less potential corrosion, acid rain paint damage; interior water damage: windows, sunroof left open, leaks
* from impacts:
~~ while parked: collisions, scratches/nicks/scrapes from vehicles/bikes/pedestrians; bumper dings from other parallel parkers
~~ while parking: curb-related wheel, tire sidewall, lower body and passenger door bottom damage
* lower risk of theft and vandalism

saves time and trouble:

* you always have a space, and the same one
* accessing and loading vehicle--closer to apartments than street spaces
* no condensation to clear from windows on cold/humid mornings
* vehicle is on private property--lower risk of:
~~ neighbor conflicts
~~ parking tickets/towing:
~~~ red/yellow/green/white/blue zones, time zones, street cleaning, permit required, distance from curb, wheel not cramped, etc.
~~~ no need to move vehicle weekly i.e., while traveling, vacationing, biking to work, vehicle needs service etc.

safer:

* lower risk of you and your passengers being struck by vehicles, bikes while accessing
* well lit at night, vs. random street space lighting
* accessing and loading vehicle--closer to apartments than street spaces

lower car insurance premiums:

* due to the above; check with your insurance provider

(click to enlarge)