"Also, I suspect your idea of parking huge quantities of H20 in orbit, intending to keep a stable supply of H2 and O2 as water in orbit as potential fuel has some engineering problems. It's quite difficult, and requires alot of energy to liquify H20, even in space, where even the nighttime, or shade temperatures in orbit are not nearly cold enough to help. Electrolysis of H20 into H2 and O2 are also energy demanding."

It would challenging if for no other reason than it hasn't been done.
It would be less technically challenging to have a gas station in L points. And far less technically challenging to have a gas station on the lunar poles.
But a significant part of the difficulty has to do with the total cost of a project, so in that sense, LEO would be less
technically challenging than L points or the Moon- or at least that is my best guess.

But if you were to somehow "able" to compare technical difficulty, as compared to dealing with potential political difficulties, and/or the problems related to business challenges. I believe the technical difficulties are less significant in comparison. Or said differently, the technical challenges are less of a barrier to overcome in terms money/time.

With that said. Let's look at some of these problems you mentioned.

Or before I begin, let me first put it this way:
If you can't "mine" water from man made tanks of water in LEO [in order to make rocket fuel] you can't mine water anywhere else in Space.

So, you said:
"It's quite difficult, and requires a lot of energy to liquefy H20, even in space, where even the nighttime, or shade temperatures in orbit are not nearly cold enough to help. Electrolysis of H20 into H2 and O2 are also energy demanding."

As far as I know liquefying H20 wouldn't be much of a problem. And I assume that with the proper thermal design, tanks of water could passively remain warm enough to be in a liquid state. But if not, then warming them shouldn't be too hard. Though as a note, it might be easier to send the water to orbit, if the water is sent frozen.
As far as Electrolysis, I believe it's some where around 4.5 kw/h per kg of water. It's a bit complicated due to various catalysts and methods one might use.
Let's assume 2 to 2.5 kwhs per lb
200 tons: 400,000 lbs 800,000 kw/h to 1 million kw/h.
So, if you have 20 kilowatt solar array that takes 40,000 to 50,000 hrs of sunlight. You would get more than 12 hrs a day, but if at 12 hrs a day it takes 3333 to 4167 days- around 10 years, or 100 tons per 5 years and 20 tons per year.
As I said, you could charge $2000, $4000, or $8000 per lb
Or 4, 8, or 16 million per ton.
So per 20 ton per year: 80, 160, or 320 million dollars of rocket fuel per year.
Say your cost is roughly 1 billion dollar- you are in the red 1 billion dollar by the time you have the 20 tons of rocket
and you selling it- 320 million per year thereafter might
be excessive in terms of profits and perhaps no one will buy it at such a price, 160 million could a reasonable return, and perhaps you would have buyers.
You might be only 1/2 billion in the red, and sell at 160 million per 20 tons, or perhaps 80 million per 20 tons.
If you selling at 160 or 80 million per 20 tons, you might have enough demand that you need more solar panels [or some other way getting electrical power].

Of course if instead it cost 2 billion dollars you could go bankrupt. Though if it only costs 1/2 billion you could also go bankrupt.