Can you buy a sat nav (tomtom/garmin) that not only alerts to fixed speed cameras and remembers spots where mobile camera vans park, but does the same job as a full on camera detector (road angel/snooper) and will pick up on lazer scatter up the road as well.
no 
Even if you could…
A) You shouldn’t be speeding anyway
B) By time any of those has picked up the laser, it’s too bloody late, you’re already done.
Tomtom (and most likely others) do a ‘premium safety camera’ which includes fixed and mobile points for cameras. But, it’ll warn you at every point where a mobile MAY be situated, in the end you just ignore it.
And if like me your a camera spotter, then you get lifetime free membership of the database on the PocketGPS forum.
Ken.
Don’t bother with lazer it’ll only tell you you’ve been done most don’t actually pick any scatter up as the beams are very confined
There is a website which gives the locations & times of all mobile camera vans but I don’t know what it is, you’ll need to google it.
BB