Neighbor's Tree Led to Foundation Issue

[Razmig Yeremian]

Hey all!  As posting states, I'm currently dealing with an issue stemming  from my neighbor's lot: since 2016, having purchased the home as a shell property, the property owner did next to nothing to repair and/or maintain their building structure or backyard.  As a result, a tree has been given free-reign to grow uncontrollably in the small, 20'x15' backyard space -  which now has roots that have penetrated not only my basement walls, but the neighbor's foundation on the opposite side of the property as well.  These are Philadelphia row-homes.

According to my neighbor, effort has been made since 2016 to have this issue dealt with by the property owner, even going so far as to involve L&I as well - to no avail.

I decided to reach out to a real-estate lawyer I dealt with some months ago for an unrelated matter, who recommended I reach out to an arborist as well as a foundation repair specialist to estimate costs for remediation.  To remove the tree I would be looking at an expense of $5800 and to repair my foundational issues, I'm looking at roughly the same cost; so overall, this is looking like an expense of $11,600 for just my property.  I imagine my neighbor will face a similar charge for their parcel as well, excluding the tree removal.

What's most frustrating about this situation is that the property owner has hundreds of parcels in and around the Philadelphia area, so I would imagine affording the cost to remove this tree wouldn't set him back.  However, for people such as myself and my neighbor, an elderly, retired woman living in a low-income neighborhood, we would be depleting capital otherwise used to support our living expenses.

Has anyone in the BiggerPockets forum faced similar situations in the past?  If so, how did you overcome what seems to be negligence on the behalf of the property owner and the city in which the parcel resides?  Any suggestions and/or feedback would be greatly appreciated!