I just completed three costly upgrades in terms of population for my scroll MFS to level 19, but i am no longer using them. Can I ignore upgrading them in the future? Maybe I should start building planks, crystal and silk MFS? I can never get those in trades.
Pauly7 did answer you, so I'll just add numbers.
- Your boosted scrolls manufactory produces 7x the amount of goods of the regular scrolls manufactory (accumulated 500 scrolls relics = 700% production boost).
- That means that for each 4000 crystal or silk you would produce, you could have produced 28000 scrolls in the same space used.
- If you put those 28k scrolls on the market in the worst possible rate (1:4 I believe), you get 7k crystal or silk for your 28k scrolls. I do believe such a trade will be grabbed almost instantly. However, there is no need to go that low - I'd start with the ratio suggested by Pauly7 and add bigger bonus only when the trades get taken too slowly or not at all.
- In any case, I'd start thinking about switching to non-boosted manufactories only if all my trades were left hanging there no matter the ratio I offered.
Note1: The numbers chosen are just an example, they divide nicely by 4 and 7. It wouldn't be as nice with 1000. ;-)
Note2: Today I read short remark about people reducing the number of scrolls manufactories and increasing the number of their boosted T1 and T3 manufactories to cross-trade for crystal and silk. That's an interesting approach and it might be quite efficient.
Note3: Yes, I know, even the non-boosted manufactories can be somewhat boosted. The Mountain Hall wonder boosts production of all manufactories. However the maximum (level 35) boost is 284%, meaning scrolls and silk will give you 2,84x the amount of goods and scrolls will give you 9,84x the amount of goods (700% + 284%). That reduces the difference, but you need few tens of thousands KPs and a lot of goods to get there.
Note4: Until the Library set was introduced, there was shortage of scrolls on the market all the time. However in my opinion the current (opposite) situation is even worse!