Well, like I said, it would be best to make satellites telepresence on-orbit serviceable. Also, advancing technology will result in greater inherent reliability and the ability to include more redundancy.
There's not a lot to be easily found on the cost issue since most of what I found always talks of total cost to orbit, but I found this from 2009:
https://www.space.com/6839-space-forecast-predicts-satellite-production-boom.html
"The average satellite price over the next decade will be $99 million, compared to $97 million in the past 10 years. The per-satellite launch price is predicted to remain flat, at $51 million, according to Euroconsult."
Note that that $51 million figure is for expendable vehicles which don't have the need to put a lot of non-payload mass (like wings) into orbit and return it to Earth, factors which make winging vehicles inherently more expensive.
Now, a vehicle that simply used a cheap ride to space on a Falcon 9 or FH and ballistic reentry which delivered payload to space in its payload bay and then robotically or via telepresence loaded a satellite to be returned into its payload bay might be economically viable, but then the satellites will need to have some standardized handling and attachment system amenable to robotic handling.