Unless they are used as strictly temporary measures, rent-control ordinances (municipal regulations placing limits on rent increases) have several negative effects for renters.
Facts
conditional + causal (unless, effects, will bring)
use rent control >> shortage of rental units over longer term (and other neg effects)
comparison
Bad effects (long term) vs. Good effects (short term)
conditional (all, invariably)
tenants have political power → guided by to enact/repeal rent control short term
Evaluate
There were conditionals and causal ideas and a comparison. Where to begin?
One starting point could be focusing on the Overlapping Concept in the last two claims about short term vs. long term gain.
In the final sentence we hear that tenants's desire for short term gain will guide their decisions about whether to create or get rid of rent control ordinances.
Okay, the previous sentence said that rent control has short term gains but long term problems.
So putting those two sentences together we're inferring that when tenants have political power, they'll choose to use it to attain short term gain, and rent control ordinances provide short term gain. So they'll likely choose to enact or retain rent control ordinances.
We can layer onto that the fact that by doing this, they're bringing on several long term negative effects such as a shortage of rental units.
Goal
We could probably go as far as to say that when tenants have political power of rent control decisions, it will eventually lead to a shortage of rental units.
Let's look for something we can definitely prove.