If you have a hydrometer and are able to check your gravities and would like to know what you're looking for instead of relying on the bubbling, see below.
OGs / Original / starting gravities
Ciders, all types – 1.042 +/- 2pts
Next Batch Ginger Beer – 1.038 +/- 2pts
Old Fashioned Ginger Beer - 1.042+/- 2pts
Elderflower Beer – 1.046 +/- 2pts (assuming this kit contains a 200g dextrose sugar pack, if not gravity will be approx. 1.039)
These can vary a little from batch to batch, and also depend upon the accuracy of top-up water addition.
FGs / Final gravities
Ciders, all apple-based (inc. mixed berry) – 1.002 +/- 2pts
Ciders, all pear-based – 1.006 +/- 2pts
Next Batch Ginger Beer – 1.004 +/- 2pts
Old Fashioned Ginger Beer - 0.994 - 0.998
Elderflower Beer – 1.006 +/- 2pts
Again these can vary – and as always, the important thing is to make sure gravity is stable before bottling, ie same reading over (at least) 2 consecutive days.