Put VacationController.iff in the downloads folder.  It will enable Build Mode and Buy Mode
to be used while on vacation.  There IS a catch though.  Once you save a vacation lot with a family
on it, and exit that lot, when you get back into the lot, Build/Buy will be disabled.  There is 
nothing I can do about this.  Just have the sims visit another lot for all modes to be re-enabled.  Also, the special
Vacation Island objects will need to be purchased while a family is not on the lot.  In other words, the
buy mode that is added here is the same one as the buy mode at a sim's home.

Http://www.simsos.cjb.net

Special thanks to Dr.Doofus.