A Non Immigrant Visa can be valid for multiple entries and up to one year.
But beware: than one entry is always meant only for 3 months. Then it's to make a border passage and to pick up a new "3 month mark. These are organized in Thailand Border Crossings well. In southern Thailand are several daily buses, minibuses and taxis back to the Malaysian border, and again. Particularly hard-boiled may also use their own scooter to make the trip ....< br>
The last entry makes it a rule shortly before the expiry of the visa and thereby gains again for another 3 months. Then you have to worry where and how to get a new visa, so it stands on a trip to Germany, Malaysia or Singapore, where people at the Thai Embassy can issue a new, provided it meets the conditions.
Warning : Make sure each entry, whether registered in the passport stamp with the correct date, for 90 days. For the date in the passport is binding, otherwise you risk getting an expensive "overstay".
Oops reporting: Foreigners who enter with a non immigrant visa and
private stay reportable within 24 hours after arrival at the immigration. This "message" is repeated after
each entry and must normally be completed by landlords or with tourists from the hotel / resort. As the owner of a house but may not mitbekommt when I am out of my Germany vacation, or wherever entry of foreigners here must sometimes take the initiative and report to the landlord or immigration. See corresponding page of the Immigration
90 days reporting: Foreigners who need to stay over 90 days in the country, also report to the immigration. But this rule is really only for foreigners who have a longer residence, as members coming to a normal visa even before the expiry of 90 days. The day count begins with the entry back to zero This again the side of immigration.
The legendary "Annual visa" does not exist. There is only an extension of the above non-immigrant visa for up to one year under certain Requirements (his own company, appropriate balance, regular income from abroad), for example, pensions and so on.
For a more detailed listing of all Visa and prices here is the relevant page of the Royal Thai Embassy linked in Germany.