I think R0 for the flu is usually take to be in the range 1.4-1.6 and for the common cold, 2-3. It's significant that it is quite a bit over 1, as it wouldn't spread so effectively if not.
It's an exponential factor, so small differences in the value make a big difference.
On the other hand, R0 for SARS-Cov-2 has been estimated as high as 6 by some groups.