What does widening your driveway consist of? For example, are you tearing out old worn concrete and pouring a new wider driveway, or are you just pouring a 1’ strip of concrete on each of the outer sides. Are you looking for a way to keep it from looking patched?

Thanks for info. Yes, remove the retaining wall as far into the driveway as the driver's door would hit it. The wall looks lower relative to the driveway nearer to the plant in the way back. Also, talk to your neighbor when your car is parked in the driveway about how much space your passenger door needs to open. A coordinated pruning effort involving both of you can be friendly. Bring cookies. If you can't remember exactly who owns what, review your house-buying documents (the official ones) to see if there's a description of property lines that's useful. Many neighbors are cooperative and reasonable when it comes to pruning.

There is not enough room for a car to drive around another car parked on the driveway. Grass block pavers is what you need. Make a grass block parking space left of the drive, parallel to the house, a left turn in. You will be able to back out of this parking space onto the drive and exit going forward. Working off the tree ring create a narrow bed along the street side of the grass block parking space if you want to screen it some. That will have less impact on resale and people will just have to enjoy your curb appeal when you are not parked there. Tileco 11.5 in. x 17.25 in. x 3.5 in. Concrete Grass Block Paver-4GB - The Home Depot

I don't know why some commenters are talking about a new pathway - a sidewalk - to the street. The OP never asked for that. Also, never asked about additional parking. Simply, if you measure a parking space at your local grocery store, it probably ranges from 9' wide down to 8' wide. If you're lucky and it's 10' wide with the double lines then you feel much more safe from dings in your door, and can step fully out of your vehicle, right? Now, a typical residential driveway width is 16'-18'. So think if you drive up the left side and park outside and leave room for the 2nd car on the right. If you were playing the "lava" game and not trying to walk on the grass, you'd have to shimmy out just like in a skinny grocery store parking space. Adding a border will help with that, as well as looking better to many people, and will not accentuate the garage as being more "in your face." I would argue it actually brings the scale down if you choose colors/materials that accentuate a design element of your house, regardless of how wide the width of the driveway actually winds up as including the border. Here are some examples of a border: