Hello from north central Alabama St. Clair County. Your property sounds amazing but I'm one them crazy plant people. 🙂
What plans did you have to do on property, did you intend to landscape or be minimalist with lawn only? Might be helpful to wait if possible to let a growing season pass and mark anything ya wanted to keep. The previous owners hobbies, and commitments where his journey in life not yours. Now that you know the history and folks expectations of the property how does it all make you feel? If you feel antsy, and overwhelmed thinking bout it, if it all makes you have feelings of dread then amending your feelings is more important than appeasing others. Check with the Master Gardeners program in your county extension office. They usually have two plant sales a year to raise money for the program also local gardening clubs do the same. They would come and get most off what needs dealt with I'm sure, and you get the bonus of meeting great folks and gaining knowledge and possible ideas from them. In the end I doubt the old fella would want this to be a burden to you and would tell ya it's ok to let go. If your in the Tuscaloosa area I have a friend there who would probably come and give some stuff a new forever home on his property. If you are close to Ashville St. Clair County I would be happy to come and i.d. things and suggest usage. Hope ya find the answers you seek and they foster feelings of contentment.🙂