one inflated balloon with helium I think is around $3.50. I go here for party supplies but last time I needed balloons I went to m&m balloon co. just south on 99... really great prices/ selection and they offer "ultra float" to make the balloons last several days! :)
one inflated 11" latex is $1.39 and to extend the life and seal the helium in longer, hi-float is another .30 per balloon. without the hi-float the latex will last up to about 12 hours and with the hi-float it is guaranteed for 24hrs but usually will last longer.
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