Hello,

i am 181.5cm, inseam is 88.5-89cm, torso about 63cm. Arms length pending on where you do it, 66.5-67cm.

I based my sizing (stack and reach) on my 54 size Scott Foil (stack 549mm/ reach 385mm). I also use 35mm spacers, a stem of +/-6 degree, 120mm long flipped (flipped equals 26mm + in height). 549+35+26=610. This also shortens reach. I am not upright as my saddle is high. I use look blade (stack pedal and cleat + 17mm).
Saddle to bar drop is 100mm.
Saddle is now at 780mm, i could go a bit higher actually. From ground up, saddle 1030mm, bar 930mm.

Most bikes get too short in height, or height is good but reach runs to long. I have many stems and i have tried positions like crazy.
Yes, i should really need a good bikefit. But those i really trust do it well are two. It is very very far and going back and forth wouldn't be done in one day. I've seen several customized bikes, were people ride with flipped stems, too much spacers and i just don't get the idea if they do it that way.
I can ride the bike with minimal spacers and stem in low position. I can tell you, to sit as i do now really affects some of the bikes cornering and descending. The feeling i am on top is not what i'd like. Next is, i would like a bike that is more pleasing. The Foil is not, it is a bit harsh. Yes, from what i've heard of Bianchi Infinito CV it seems to be a very very good bike. So no question, i would pick that frameset also if i could.
Paduano sells their bike as frame with seatpost. You buy the saddle adjuster/clamp and the fork and the headset.
You also decide if you want carbon or titanium; seat tube, seatmast, down tube and toptube.
It is more expensive the more carbon you'd like. Also you can go for a more elastic layup in tubes, or stiffer. Stiffer cost most as option, elastic is a milder cost increase. To run electronic you need adapters. You can also buy an even more expensive version made for disc.

Most custom i have looked at is from US. It is not that i must have custom, don't believe that. I just did not find frames with the height and length that seem suitable for me long leg/ short reach fit. I have been trying some longer reach, but it affected my lower back.
What eats me in long time riding Foil is the hard seating. It is to much for me. I have asked alot regarding this and some claimed i was better off looking at a full ti bike. This is where it all began. An import is always tricky as we have so high taxes for out of EU imports.
It is well around 35% of the frame and freight cost. Nothing is written in stone when it comes to frame. But to really ride a bike and feel it, i'd need my pedals/shoes and bibs. There are very few offering such a test ride.
I would take Infinito CV over Roubaix, but Roubaix is also interesting. So is Cannondale Synapse (new), Scott Solace and Rose Team CGF and many more. I have to rid most bikes from my list due to frame height. I won't buy a bike to low again (and not to long either).