I have a very decently paid job here in Germany. After taxes, health care and all the other deductibles I take home somewhat around 30 - 35 Euros per hour. As overtime is included in my job (I work hard not to do too much, but still) having fun building something like that on a weekend would also be an economical bargain.

I still am totally in line with my sister comments in valuing the fun building something and understanding a few things a bit better in the process quite higher than the economic aspect. This would only be the icing on the cake.