Belgium

Taxation and social security will determine a lot of what you do in Belgium until you have accumulated enough assets:

• Labour taxation is extremely high and progressive. Some very narrow and specific exceptions are really worth exploring, like flexi jobs. These may provide the loopholes to enable ERE. https://raw.githubusercontent.com/markvdb/markvdb_public/master/side_gig.png is slightly outdated, but may provide a good starting point.
• Capital gains taxation is almost non-existent for some asset categories. Use this to your advantage!
• Social security is quite generous. Examples include:

 * unemployment benefits unlimited in time
 * being unemployed builds you a fairly ok state pension too
 * excellent, mostly government subsidised health care

Useful resources:

• Bogleheads wiki: investing from Belgium
• BEFire reddit