The only way to stay "legally" is to start the Residency Process at the Dominican Embassy or Consulate in your home country. There are many "hoops" to jump through, including getting Criminal Background Checks by either the FBI or Interpol, which have to be appostiled, translated and submitted with your Residency Application. You'll need a translated and appostiled copy of your legal birth certificate, a marriage certificate if your married and proof of solvency, which can include ownership of property here in the DR or a guaranteed income that can be verified by the Immigration authorities. The process is lengthy and can cost several thousand US dollars if handled by a respected attorney here in the DR.