While I have zero experience in STR "innerhalb von Deustschland" I am curious as to why these specific areas- and while I don't know SFR legislation per region, with STR in mind I might only suggest to look into Berlin as a more lucrative area- thinking along the lines of tourists specifically.   

I think you're aware the PM fees for STR are on average higher than long term rental PM fees (it's just more frequency of work), but really it's going to come down to city legislation and the building condo association. 

However I expect Legislation will be drafted by states to deal with the significant number of evictions that will add additional roadblocks for landlords. 

Title search, back taxes etc all come in here as well.If you've covered any major defects, established rehab or updates needed in terms of cost, run accurate comps, verified tenants/PM's if this applies/they want to stay, verified zoning if it applies, tax rates/title work, local landlord legislation for buy and holds, and the terms of the contract, you should be ready to rock and roll = ) Hope this helps!

@Anthony TranYou will run into what is called circular legislation.  

Fannie Mae and the National Association of Realtors predict housing prices will rise slightly this year7, while Zillow expects them to fall between 2-3%.8 Still, that would be a far cry from the double-digit declines that occurred during the last recession.9Government Intervention Will Help Stabilize the MarketPolicymakers have been quick to pass legislation aimed at preventing a surge in foreclosures like we saw in 2008.

Unhappy special interests got legislation passed that said "only if the owner redeems" and the law was specified as retroactive.I am paraphrasing, but the recent decision said, "You cannot just pass a law and make it retroactive and deprive people of their property rights with a wave of your magic wand!"

Since the ADU laws in CA included multi-family properties in 2020, we have been working with owners and managers across California to develop multi-family properties with ADUs, in various ways within the constructs of the current legislation.

Bonus is they advocate for landlords so our legislation doesn't gear entirely towards tenant-friendly laws.

Final legislation is to be released.