Im setting this up right now on my balcony, which will make me the third apartment in my building to install a system like this.

All you need is some standard solar panels (they all use the same connectors so you can mix between brands often) and an inverter box.

I got three used panels for 10€ a piece a few months ago which i will slap on the outside of the balcony.

This 800W grid synchronizing inverter can be had for 100€ currently and even has two MPPT trackers for separate panel strings (for when not all panels are oriented in the same direction).

This is what the end result typically looks like: