A rule of thumb seems to be 2 and 1/2 months, I am not too sure though as that seems a lot.
couple months pay...or...i hear Cubas real cheap
She buys mine.
That depends on how much you spent on your fiance...
What you can comfortably afford. What comes from the heart is the most important
depends on how snobby she is.. or how generous you feel..
do try to have something left over for basic necessities like food and bills..
There is no right or wrong amount, as long as it's something chosen with her and her tastes in mind.