BALLARAT families are being forced to live in caravan parks as the number of vacant rental properties dramatically shrinks.Figures released by the Real Estate Institute of Victoria show the regional rental vacancy rate has dropped to just 0.7 perthcent.Three perthcent is the accepted measure of a balanced market.Tenant Union of Victoria policy and liaison worker Toby Archer said the figure spelled doom for renters in Ballarat and the central highlands."We are seeing a boom in the number of renters being forced into insecure and inappropriate accommodation in caravan parks because they simply cannot secure a rental property," he said.REIV Ballarat division chairman John McMahon said there were a number of reasons for the drop in the vacancy rate."There has been significant population growth and quite a lot of people moving to Ballarat have done so for work or study and haven't settled here as permanent residents, consequently renting as opposed to buying," he said."Also a lot of first home owners, especially in the last 12 months, took advantage of the high first home buyers grant and while some built new houses, still quite a lot of them bought established housing and a lot of that came off the rental market."And some people who were first home buyers and bought six to 12 months ago as a rental property, have moved into it."Mr McMahon said the situation was only going to get worse over the new year with an expected influx of new residents."Some people might opt to purchase if they can't rent, but there is a shortage of stock; we're really facing a crisis," he said.