Last summer we put new panels over sunny side of our 20yo terracota roof. Since the roof is just overlaid "bricks", we only had to remove some of those, use screws to fix hooks to underlying structural wood, and put the roof tiles back on. On the hooks we install metal wireframe, into which the panels were seated and fixed.

Apart from raising the panels to the roof and fixing them in place (brother helped), we did it just me and dad. Panels are just too heavy/bulky for 2 people.

The terracota roof have 0 new openings, as the hooks are in the space where two tiles overlay, so there is 0 fear of long term damage trough water ingress. The hooks and aluminum wireframe fixture were the most expensive part of roof instalation.

So, cheap, fast (3 weekends total?), and fun. I am surprised some people have totally different experience