Not quite one time only. A bit pedantic, but you can turn holoemitters on and off. I've got the freighter one I bought months ago sitting around with 4 minutes left on it. There is no way to refill their timers, though, once the 15 minutes is up they're gone for good and it's back to the dabo tables. And it can take quite a while to save up for even the mid level ones.
Well, the only thing to do with latinum is to waste it, really. The only things you can spend it on is holoemitters and trophies. Though I suppose having a pile of 500,000 latinum sitting in 10 Forward is slightly less wasteful than a 15 minute disguise that doesn't fool sensors.