Most of us will probably continue to collect what we collected before the euro cash came. For many collectors in Germany, for example, that would be German and maybe Austrian coins. Others, especially new collectors, try to get a complete collection of the circulation coins from the 12 member states or even from the 15 countries that issue euro coins ... Christian
The Vatican, San Marino and Monaco Euros are issued in very limited quantities. One can expect to pay around €200 to €400 for a complete set. In building a set from each of the 12 countries, the most challenging to find (at least here in Germany) are Finland, Greece, Portugal and Ireland. So I would say those would be the most desireable. Also, these are the most distant from the majority of Europe so finding them in crculation in the remaining 8 countries can be a daunting task. I have been putting together 2 sets, one for each of my children since the Euro's introduction.