I had the same problem to find an apartment in Zurich and started scraping several websites to automate the process. The tool is at https://www.immomapper.ch perhaps you find it useful.

When searching for an apartment in Switzerland a few years ago I found no good listing aggregator. So I built https://www.immomapper.ch/map which crawls the largest providers and currently shows over 100'000 listings on a big map with filtering, email alerts etc

http://www.immomapper.ch/ - It's a meta search engine for rental property in Switzerland. Real time filtering, price comparison to rentals in the neighborhood, etc

Switzerland is a tiny market, have been thinking about expanding to other countries...