Probably not much of a change due to Trump. Real estate is so localized that most federal based policy changes don't have massive influence.
I can see him (semi-)privatizing Freddie/Fannie. Depending on how it is done and what guarantees the government offers and requires of the released entities, interest rates could move slightly higher. Of course, that could be offset as he works to reduce inflation. Given his spending habits during his first term, it might be a wash.
Costs to build new properties will probably increase. Tariffs on goods and potential reduced labor force (illegals being deported) to build.
I can't see changes in S8 benefits. Public has little desire to see them cut and GOP has no desire to increase funding for this.
Far less FHA lawsuits against landlords. The BS discrimination claims (you won't rent to felons, and blacks are more likely to be felons, therefore you're a racist) will go away.
If mass deportations were to actually happen, it could slightly ease demand, mainly in larger cities, but probably not enough to change rent rates. I could see a requirement, perhaps under the Patriot Act, that requires all landlords to get a SSN/TIN from everyone living in a unit and report that (or lack of) to the federal government. That would bypass many city/state regulations that force landlords to rent to people here illegally.
Overall, it's going to be up to the state and local governments to enact changes that will affect the local housing markets. I don't see much of that happening.