If you're talking about end of Fannie Mae (and others) conservatorship, then there could be significant changes to how conventional mortgages are structured in the US (ie, you might see less 30 year fixed). It could also lead to an increase in the cost of a mortgage which could (1) price more people out of the market and (2) as a result lower the price of properties. The positive flip side to this would be more renters needing places to live since they're prices out.
All of this, however, is totally speculative. I by no means intent to make a political statement, but.... As with all things related to the government, this will not be a fast process (and could be changed again in a future administration). The government's involvement in the housing market is deep and invasive - despite the current administartion's intent to move toward undoing the conservatorship, there are many who want to maintain control - the process won't be a clean and fast one. I may well be wrong, but I would never bet on DC moving quickly on anything (except congressional payraises).