Too, As Well, and Though

[Arushin]

If you have too, as well, or though at the end of a sentence, is a comma always placed before them?

I have that couch, too.
I have that couch, as well.
Mine is in better condition, though.

?????????????

[2006]

If you have too, as well, or though at the end of a sentence, is a comma always placed before them?

I have that couch, too.
I have that couch, as well.
Mine is in better condition, though.

?????????????

I wouldn't use commas, as they serve no useful purpose.