I hope you will find someone to help you! Make sure you report back what happened!
I caution you about the choice of dances though.
They are both fast so if you are planning to do a dance for more than 3 minutes (I assume a mix of he two, maybe with the music mixed as well?) it might be a challenge to look impressive till the end.
Secondly, ChaCha is stationary while Samba is moving around so care must be taken to end up at te right spot for a good transition. That is I would rather not start a ChaCha in the corner or a Samba in the middle of the floor. By the way how much room will you have?
May I suggest two other latin dances for consideration: Rumba and Jive. Rumba is slow, it is the easiest for the man to get his feet wet IMO (big plus if your fiance has never danced before).
Jive is usually a crowd pleaser and it is technically the least demading I think. (Mostly stamina required, in comparison Samba tecnique is much more challenging. You want to look good right?)
You could start with a Jive for 30-45 seconds switch to Rumba for 60-90 seconds with some nice dips etc.and finish with a Jive of 30 seconds again.
Matyas
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