Just had a look on Thomann. For one of each of the modules they’re listing it comes to £527 which wasn’t a bad guess! That gets you the following modules
112 - dual vco
121 - dual vcf
130 - dual vca
140 - dual envelope
150 - LFO/sample & hold/noise
173 - quad gates.
Obv need to factor a case into that plus patch leads etc. All in with their Eurorack Go case it comes to £760. It’ll be interesting to see if in time Thomann start selling systems akin to the standard off the shelf offerings from the likes of Doepfer etc.