I purchased equipment for landscaping to do basic maintenance required by zoning laws, which is not my responsibility because I was asked and assured compensation and have yet to be paid and am still being asked for back rent. I have also done other work that isnt paid
I think that purchasing landscaping equipment for your landlord's use and benefit would only qualify as an improvement to the property if the equipment was incorporated into the property. For example, if you installed an underground irrigation system in PA per a verbal contract, that improvement is eligible to filing a lien. However, if you purchased a hose and conventional sprinkler for the landlord, it would be less likely to be deemed a lienable improvement because you could simply take that equipment back if you were not paid. If you are still renting the property from the same landlord, why not just provide a written record of the costs of the equipment and reduce the rent accordingly?