We once upon a time discussed the different views of the Rambam and the Ramban with respect to the mitzvah of building a mishkan. The Rambam opens his Hilchos Beis haBechira by describing the mitzvah of building a "bayis laHashem" which is "muchan l'hakriv bo korbanos", a place designated for sacrificial offerings. The Mishkan and Mikdash have a clear and defined purpose. The Ramban, however, defines Mikdash/Mishkan as a model of the Har Sinai experience, a place where the Shechina is revealed; it would seem korbanos are secondary to that purpose or just a means to elicit a hashra'as haShechina.
Parethetically, last Shabbos the 5T had the privilege of hosting my rebbe, R' Blachman of KBY, and he mentioned this Rambam while speaking on Friday night. R' Blachman seemed dismissive of the idea that the Mikdash's purpose is korbanos -- korbanos are what are done in the Mikdash, but they are not the Mikdash itself. The Mikdash itself is defined by the Rambam's words "bayis laHashem", which R' Blachman suggested (based on a Tosefta in Zevachim) is means the place of the aron. I did not get to ask, but I am not sure how this reading makes sense of the additional words "muchan l'hakriv korbanos" -- why introduce what is done in Mikdash here if it is not a definition? Leave that for Hilchos Ma'aseh Korbanos, etc.
Perhaps there is another element of meaning to these words "muchan l'hakriv bo korbanos". Rashi explains "v'yikchu li Teruma" to mean that the mitzvah must be done lishma, strictly for the sake of Heaven and for some other personal agenda. The Rambam therefore perhaps stresses the purpose of Mikdash in the opening to these halachos in order to emphasize that it is this purpose alone which must guide our intent in building a Mikdash (I am not familiar offhand with another place in Hil Beis haBechira where the Rambam codifies this rule of lishma).