Single source is anything that lets you get more than one
output from one source, be those outputs ten different webhelp
outputs or just one and a printed document output.
You can have as many webhelp outputs as you can manage. Right
click and add new ones or copy existing ones as a base.
Best practice depends on your content. You can have different
TOCs for each output or you can have a smaller number and apply
conditional tags. So with say 10 outputs you could have just three
or four TOCs and apply conditional tags to vary them. It's whatever
works best for you and can be understood by anyone you work with.
The scenario you describe would be ideal for the way RH
works.
The title bar and browser tab take their text from the
Project Title in Project Settings so you will need to change that
for each output.
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