The primary difference between quasi-experiments and true experiments it ths quasi experiments typically

The differences between true experiments and quasi-experiments is that in a true experiment, participants are randomly assigned to either the treatment or the control group, whereas they are not assigned randomly in a quasi-experiment. Quasi experiments are empirical interventional study used to estimate the casual impact of an intervention on its target population without random assignment. 

Well let's uhmmm how many bedrooms you want. if you want a garage. not to mention the price of the house?