Using garage door remotes as a voting system?

I'm putting together a talent show and want to have the audience vote
for the contestants (on a scale of 1 to 4 would be fine) using wireless
remotes (maybe even garage door openers?) The results would be
received through a computer system and then projected on a screen.
Does anyone have any suggestions as to how such a system might be put
together? Someone told me I should use a heterodyning receiver. I
found a site that seems to have some of the elements:
http://www.automicro.com.tw/ Any ideas as to which samples I should
buy? Thanks for any info or suggestions!

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