Adjacent Property Encroachment

[Chuleung Leo Joo]

Question,
Recently purchased empty land, survey indicates neighbor property fence encroaches over few inches to 8+ feet in major area, and another approx. 1,800 sf. parcel off from out empty land.  what would be the best way to approach for them to correct the fence location?  is there any professional who resolves this issue.  we are about to initiate a land development shortly and this needs to be resolved.

Thank you, in advance.