Well, i am one of those lower level players you are mentioning about that are making so much of these products to sell (and i can say that i almost exclusively only sell premiums) and it worked well for me, BUT because they do take so long to make and sell, so it really annoys me when one single person without a care buy all and didnt consider about other players that are in my list.
I am a newbie, i just started this back in late august but i do pick up things fast.
The thing is, got to have a plan. I expand slots on my sugar and dairy, i have a par set for every item in my inventory with the exception of expansion items.
Sugar and dairy items are on a par of 2:1 meaning if i plan to make 10 of X cakes for example, I will have 20 sugars. and I never go below >/< 5 of my par.
I dont care if people open sugar crates although its frustrating because I do like to help filling boats and i am working towards COOP 3 (i am around 300 helped atm) so those sugar and dairy slows me down. But I dont fill them nor i ask for them.
Anyhow, I also have slots on almost all my machines expanded a few times with the exception of the loom.
Sometimes i makes the item I fancy just cause I can but most of the time, you make the items that is most cost effective vs time spent. Even for these items that i put out on the stand, i keep a par... if i make 20 berry juice and i sell 10 then its time to "order" from the machine.
Sometimes i also buy low sell high. this do takes a lot of effort to page through the newspaper and constant refreshing by exiting the app and reloading.
I started buying feeds and also milk and eggs to supplement my own supply. The cost is negligent here. I am planning to get masteries on the 2 feed machines last. So right now, i don't really care abt it.
As for the $$ vs xp wise, i am still levelling pretty fast. I reached level 42 when? I think the day before? well i am at the halfway point already xp wise and i am selling all my stuff. If you continue to make stuff 24/7 never letting the machine rest, i check every 2 hrs fill some boats and EASY truck orders here and there, the xp do keep coming. I am picky with my truck orders i delete until i see the one thats easy items and good xp dont care abt the gold on truck orders cause thats not my main income.
If i am really low on items to sell, you will notice my stands have stuff that are produced real quick instead. For example, always have popcorn, shepherd pie, that kind of stuff... things that you make under or within the hour.
So, my stand are filled very frequently on a daily basis and this is taking in i get raided like crazy which really do annoys me more than flaming remarks on a forum lol
And thats the tl;dr of how one "low level player who sells so much of these products" does it.
does that demystify some of your curiosity? LOL
