Already answered this. If they pay less in taxes then they receive in govt handouts (such as welfare) all 4 years of a cycle, no vote. That is leeching.
Full time students, stay at home parents, etc don't get welfare, food stamps, etc. They aren't leeching. They get to vote.
Obviously no voting twice.
If your point is that these are insurmountable issues that can't be overcome, then you'll have to try a little harder. Instead, though, I think we should have a thread for this if we want and respect OPs wishes.