Kyanite
Ridin' The Range
In addition to the other suggestions, namely speaking to the neighbor, I'd let the seller know that it's a potential issue with buying the home. Perhaps it's something that the agents (if you have them) can discuss together, but if you are seeing this issue, other potential buyers did too and if things don't go through with your sale, it will be an issue for other buyers too. Hopefully the current homeowner/seller has a good relationship with the neighbor and can say "hey, your peafowl have damaged the property and their frequent presence is a problem for me selling the home."
