How small can I go?

Hello, I'm in my sixties now, but as a teenager I was a keen modeller and even designed and built my own gliders. I was Devon based and almost exclusively slope soared.

Now I'm London based with a small house, so building is out of the question and whatever I have will likely need to be stored in a small shed.  I'm thinking of trying electric powered since that's a new option for me.  I have a feeling the smallest viable is about 60cm span.  I can see there are smaller around, esp flying wings, but my guess is these are far less stable and tend to the aerobatic?

What would be the advice for the smallest beginner electric fixed wing option?

Small electrics tend to be very fast, due to the high wing loading. And - because they are small, very quickly get too far away to easily see.
First off - find out where you are going to fly the models, then get your CAA and BMFA certificates AND INSURED - before you even consider it.
Find your self a local to you club,and see what they fly, when, and where!
Also - read up and learn about the care, storage, and charging of lipo batteries, or you could find you are 'enjoying' a bonfire in the middle of your carpet!

I still rate the FunCub as the best all foamie flyer.

"Small" may work in a limited area but rather better is "slow". Slow also means you can fly keeping a bit closer to you. The problem is a small plane can be hard to see when it is end on to you line of sight. A more "bulky" plane tends to overcome this problem hence something like the FunCub as Klippy suggests.
Not a FunCub but my own foam creation.
 
100cm span yet it only weighs 242g so it is a true slow flyer. Nice and easy even for my 78 year old eyesight. .

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