We study P colonies introduced in \cite{kel2} as a class of abstract computing devices composed of independent membrane agents, acting and evolving in a shared environment. In the present paper especially P colonies are considered, which are homogeneous with respect to the type of rules in each program of agents. The number of agents, as well as the number of programs in each agent are bounded, which are sufficient to guarantee computational completeness of homogeneous P colonies. We present results for P colonies with one and with two objects inside each agent.