#2 - You can get a Wein optical slave for about $30. That is less than the price of a Safe Sync not to metion the sync cord. So option #2 is also a lot cheaper than option #1.
#3 - The Chinese RF slave I have was about $20 + $10 shipping. On top of that I had to make a 1/4" F phone plug to M HouseHold adapter ($3.66), which you can buy for about $20 if you don't want to/can't make it. You can go top drawer with the Pocket Wizard for about $300, but for casual home use, the cheap Chinese one works fine.