Hong Kong - Macau - Shanghai - Beijing

Hi. I will arrive oct 15 at Hong Kong then to macau, then to shanghai then to beijing out oct25 back to my country. Im Honduran traveling. I understand Hong kong and macau have landing visas, but if I have to get a visa for Shanghai and Beijing, how many entries should i get? I live in HOnduras, read costa Rica china embassy is the place to get it, but i have no one in costa Rica, but i do have family in mexico, can i get it in mexico? Thanks