I'm in MD and grew up here as well. I live in Montgomery County, which surprisingly isn't on your list. I expected you to be looking at that part of MD since it was between Nova and MD. Montgomery County is basically bordering NoVa in the parts you are looking at.
I go back/forth between both of the areas often and I mean, they are not very different as far as what it would be like to live in the areas and your every day life. I do think traffic in NoVa is much worse though, and for some reason it feels like everywhere I drive in NoVa, they are just doing never ending road work.
You are correct about the property taxes in VA on cars though. My friends in VA have mentioned that to me before. You also have to get your car inspected either annually or every 2 years, whereas in MD you only need it inspected one time when you purchase it.
Manassass is out there. It's far away from anything and you have to take 66 to get there, which again is always under construction and one of those nightmare roads you never want to be on. Sterling is like not quite as far out there but it is also quite a bit away from DC, but it is a nice area and I have a couple friends who live out that way. It just takes a while to get there from where we were in MD.
My wife grew up in Annandale and depending where you are, can be a bit shady. It's closer to DC than Sterling for sure. Fairfax proper is nicer than Annandale for sure but it will be pricier to live there too.
The general COL in both areas is pretty comparable though - housing, electricity, gas, etc. In general, in MD or VA, the closer you are to DC, the more housing costs. I will say though housing has definitely gone up quite a bit in the past decade or so. My house was purchased in 2012 for $420k and is probably worth like $700k-800k now. Our friends who purchased a house in Sterling in 2020 for like $700k was just sold for $1.1million and they only sold because they went through a divorce.
But you mention parts of MD that I personally have no interest in living. I dislike Baltimore and Towson is pretty close by to it. The only thing I really know about Towson is there is a college there so I would assume it's basically living in a college town, but I could be totally wrong.
Annapolis is a nice area and I would assume would be more expensive the closer you are to the water. I go there every now and then but it's usually downtown Annapolis just to go out for dinner or something like that. I always thought Annapolis was far from everything as well but that is probably due to where I grew up.
I had some friends who lived in NoVa that moved to San Diego for about 10 years, and they moved back here like 3-4 years ago. It's definitely much cheaper in NoVa compared to that part of CA, relatively speaking.