XVIII. Kathang Isip, Inc. (Kii) is a domestic corporation engaged in the business of manufacturing, importing, exporting, and distributing toys both locally and abroad. Its principal office is located in Kalookan City, Philippines. It has 50 branches in different cities and municipalities in the country. When Kii applied for renewal of its mayor's permit and licenses in its principal office in January this year, Kalookan City demanded payment of the local business tax on the basis of the gross sales reported by the corporation in its audited financial statements for the preceding year. Kil protested, contending that Kalookan City may tax only the sales consummated by its principal office but not the sales consummated by its branch offices located outside Kalookan City. When Kalookan City denied the protest, Kil engaged the services of Atty. Kristeta Kabuyao to file the necessary judicial proceedings to appeal the decision of Kalookan City. Atty. Kabuyao is a legal expert, but resides in Kalibo, Aklan where her husband operates a resort. She, however, practices in Metro Manila, including Kalookan City. The counsel representing the city, in the case filed in Kalookan City by KII, questioned the use of Atty. Kabuyao's Professional Tax Receipt (PTR) issued in Aklan for a case filed in Kalookan City.