You want built-in storage or "local" storage of the video
The cameras that use "cloud storage" can be cheaper but you pay monthly FOREVER if you want to see the videos
You do need electrical power, so keep that in mind, "wireless" just refers to the viewing of the camera, unless its a "game camera" or "go-pro" type
Motion activation is what you want to use, here is why, in motion setting the camera records all the time but its a 5-15second loop
When it detects a change in the image(motion) it saves that loop and continues to save until image is stable again, + 5 to 10seconds
So you get a before and after motion video clip
This saves recording space of course vs full time, it also saves playback viewing time when watching previous recordings
If camera is outdoors then you will get alot of unwanted recordings especially at night if it has infrared because moths are attracted to it, and thats motion
Also if there is any foliage seen the wind causing leaves to move will activate it, or if there is a street in the background, same thing when a car goes by
Also changes in light, i.e. sun setting or coming up
Most motion detection will have a sensitivity adjustment, which you just have to "play with" to eliminate as much unwanted recording as possible, this is TOTALLY dependent on cameras placement, there not a right or wrong setting
There is no real reason for full time recording any more, with digital cameras 1 pixel change is enough to activate and record, in the old days with analog cameras you had to record full time
Sensitivity adjustment is usually a setting for how many pixels changed
How many events will be recorded in 24 hours depends on where camera is located and the sensitivity used
You want to use largest storage available on any outdoor camera
Indoor cameras usually have fewer events