You need to know the appeal laws where you are.

I think you're confusing the quantity of items with curb appeal.

Now, people are fighting back to appeal the raises. 

Because of cost, duplexes are are a better choice and compete well with SFH and or apartments. 4.  

It’s quite appealing as a long term investment - even at today’s rates.

TX market has been a popular choice for those seeking higher appreciation.

I think a good starting point would be looking at the comps in your area (recently renovated or new construction homes) that sold around your desired sale price and in your desired timeframe and taking inspiration from there design choices. 

There may have been better choices for a rental at the time.  

The combination of Germany's stable economy, well-regulated property market, relatively low interest rates, and the opportunity for long-term capital appreciation make it a compelling choice for U.S.

This area has a unique mix of affordability, beauty, and rental potential that makes it a standout choice for real estate investment.