"There are no turnouts available ready made in numbers 4,5,6,8 or curved. Interestingly if I built an S scale layout the turnouts are available from a custom turnout fabricator but I plan to run Gilbert and Lionel Flyer on the layout so scale track is not an option. I would need to hand make over 70 turnouts. There are minimal structures available in S so most need to be custom built or kit bashed. Building a 275 sf detailed layout in S rather than O adds about 30% to the cost of the layout because there is so much more custom work plus more structures and turnouts can be used since they are smaller."
I've worked in both O scale and S scale and would suggest building in S but spacing the scenery out to O size, the same amount of buildings,bridges, etc. as an O layout but more realistically spread out with roads, fields, etc. taking up the extra space. This will lower the cost based on number of buildings and other models plus give a more realistic look to the finished layout. I'd also cut the number of turnouts in half for that much area and make the sidings, yards, etc. proportionally longer. 70 turnouts is a lot of trouble to install and maintain. Look at real railroads and how they manage with as few as possible then maybe you can trim some off the plan. If you need those 4,5,6,8,etc. turnouts there's no reason you can't have someone make them as high rail instead of scale, it just takes larger rail and different spacing of the parts. I'm glad to see someone making a new S layout as I think it's a great size to work with. .DaveB