John maximised his right to demand relief payments when estates and castles were inherited, sometimes charging enormous sums, beyond barons' abilities to pay. Building on the successful sale of sheriff appointments in 1194, the King initiated a new round of appointments, with the new incumbents making back their investment through increased fines and penalties, particularly in the forests. Another innovation of Richard's, increased charges levied on widows who wished to remain single, was expanded under John. John continued to sell charters for new towns, including the planned town of Liverpool, and charters were sold for markets across the kingdom and in Gascony. The King introduced new taxes and extended existing ones. The Jews, who held a vulnerable position in medieval England, protected only by the King, were subject to huge taxes; £44,000 was extracted from the community by the tallage of 1210; much of it was passed on to the Christian debtors of Jewish moneylenders. John created a new tax on income and movable goods in 1207 – effectively a version of a modern income tax – that produced £60,000; he created a new set of import and export duties payable directly to the Crown. He found that these measures enabled him to raise further resources through the confiscation of the lands of barons who could not pay or refused to pay. At the start of John's reign there was a sudden change in prices, as bad harvests and high demand for food resulted in much higher prices for grain and animals. This inflationary pressure was to continue for the rest of the 13th century and had long-term economic consequences for England. The resulting social pressures were complicated by bursts of deflation that resulted from John's military campaigns. It was usual at the time for the King to collect taxes in silver, which was then re-minted into new coins; these coins would then be put in barrels and sent to royal castles around the country, to be used to hire mercenaries or to meet other costs. At those times when John was preparing for campaigns in Normandy, for example, huge quantities of silver had to be withdrawn from the economy and stored for months, which unintentionally resulted in periods during which silver coins were simply hard to come by, commercial credit difficult to acquire and deflationary pressure placed on the economy. The result was political unrest across the country. John attempted to address some of the problems with the English currency in 1204 and 1205 by carrying out a radical overhaul of the coinage, improving its quality and consistency. John's royal household was based around several groups of followers.