The Free Trade Party proposes to remove all taxes except for a flat "tax" on the market value of real property. Ultimately, property owners would be allowed to opt out and use private security agencies to protect their property, and in that sense, it would be voluntary, and not really a tax at all.
Click this link to see a more detailed property tax proposal.
But why scrap all other taxes? Well the reason is that taxes that are not associated with services rendered directly to the taxpayer could never be voluntary. In other words, taxation is theft. Yes, it's theft by a majority, or more correctly, a group that purports to represent a majority, but it's still theft. When we think of restraints of trade, taxation has to come very high up on the list. We are not talking about users paying for services here. We are talking about forcing someone who buys a new shirt to pay 10% of its value at the point of a gun to those claiming to represent the majority of the people.