Legal Question in Real Estate Law in Illinois

Without a review of a number of things, the best answer is "MAYBE":

1. Are there any platted easements or restrictions around the edges of your property that prevent ANYTHING from being installed (other than plantings) such as impermeable (pavement) surfaces, sprinkler systems, etc.? This may be per plat or per ordinance. Very often ordinances prohibit installations w/in 1' of a lot line regardless.

2. Before any installations the contractor or surveyor should stake the intended locations. Most contractors will NOT run "up to" a lot line for the very reason of a later dispute they don't want to be part of and will run it up to a foot or so just "because".

3. The agreement you made with the prior owner -- are they in writing to cover things like maintenance, or just oral/verbal. You and that owner DID create easements to allow the trees and sprinklers being 50/50 on the lot line or certainly overhanging their property, but without something in writing it is difficult to prove (the mere fact of trees on the line may not prove anything) and plantings are considered moveable, just like fences. Whether the prior owner would agree to sign anything that confirms the agreement as an easement, is impossible to say. But since it is not recorded, the current owner normally would NOT be deemed to have taken subject to it (telephone wires, etc., are different).

4. You may be stuck having to file an injunction lawsuit, which could be nasty, you could lose, etc. From a practical standpoint get a local attorney involved and since the guy wants to take them down he's willing to pay somebody something to do something - so maybe he'll just split the cost of moving them, and the sprinkler system.