$table->bigIncrements('id');
старт id с 100001, к примеру //Your migrations here:
Schema::create('users', function (Blueprint $table) {
$table->bigIncrements('id')->unsigned();
$table->integer('qualification_id')->nullable();
$table->integer('experience_id')->nullable();
});
//then set autoincrement to 1000
//after creating the table
DB::update("ALTER TABLE users AUTO_INCREMENT = 1000;");