Property prices go up and down depending on supply and demand. If property owners need to sell quickly, prices drop. If everybody wants to buy in a particular area, prices rise. The good news is the property market is not as fragile as some other markets and you can minimise the effect of a downturn by investing for the long term. Other safeguards:
Every property MRD recommend is an average property in an average area. This means your property will appeal to the maximum amount of tenants.
MRD do not look at oversupplied areas. For instance, there was a large development in Melbourne where hundreds of units were sold to investors. All of a sudden a flood of investment properties hit the market. More investment properties, in fact, than there were tenants. This means a tenant can name their own price.
When MRD recommend a development, it is because MRD have completed the essential research to ensure the property is in an area in high demand with limited supply.