While many visa categories are becoming more flexible, the requirements for obtaining Permanent Residency in Thailand remain strict:

• Must hold certain non-immigrant visa(s) for a number of consecutive years. ThaiEmbassy.com
• Provide clean criminal record, health certificate, proof of financial stability, and meet criteria such as family ties, investment, or special skills. ThaiEmbassy.com
  People interested in permanently settling should ensure they satisfy all conditions and plan ahead.