Limited available space even on a large layout for a commercial district, industrial sites and residential housing, especifically if switch yards, industrial spurs, and engine servicing facifities for steam, diesel or both are to be serviced trurntable area with lead tracks, roundhouse, run thru diesel servicing building and car rip site or car maintenance /repair building. Also consider a passenger train terminal with multiple lead tracks, long storage tracks against the dumping posts and passender terminal stub end or run through.
If one had the economuic funds and available yard/property a large pole barn would solve this problem but for many of us including myself this is a dream not reality. The second issue is what wouldd be the demand for these buildings, assembled or kits, and finally the manufacturring cost and selling price from the vendor. I remember years ago when Walters marked the O Scale Cornerstone kits, good quality kits for the price,but the line was dropped in O Scale, currently marketed in HO and possibly N Scale. It is an educated guess that the O Scale line was dropped because of insufficient demand.
