B.C.
Survey your property line and have it clearly marked so everyone knows and there is no question where your property starts.
Take lots of pictures from every angle (with the lines marked) to show the state of your property before anything changes - annotate with dates, states of bushes/trees, etc.
Post a 'No Trespassing' sign in clear view.
Check the marked line frequently - make sure posts/flags are not moved or altered.
If/when problems arise - take a picture immediately and document it.
I'm not sure if it's pushy, but talk to the builder/owner about their insurance coverages and claim procedures:
1) so you know
2) so they know and
3) they have an idea you WILL expect any damages that occur will be fixed/repaired and
4) knowing this will provide incentive to not damage in the first place.
Being well prepared is about the best you can do.
The survey will cost you, but the cost is well worth it in the long run.