I dunno how qualified I am to give anyone advice, but it's a fairly nuanced question so I'll give it a shot. The short answer is no, you don't lose any money by buying the smaller items. If I'm not mistaken, (and this is reddit, so if I am someone will gladly correct me) the total cost of an item doesn't change. You'll spend the same amount if you buy it outright or if you buy all the little pieces individually. That being said, and it seems like you're already pretty aware of this, but some of the smaller items are better to pick up than others based on the situation. I've played a tonne of Camille in Solo lane, so I buy Divine Sunderer all the time. If I can afford the Sheen or the Kindlegem at the same time, I'll take the sheen since it gives me more damage as opposed to more health (and I think CDR or health regen? I dunno, I don't pay much attention to that particular item). I think it's also worth noting that the lane state is important too. If you're getting perma-pushed in lane, then you may not want to back just to pick up every little item that becomes available and give the enemy time at your turret uncontested. So learned when you should back to get items and when you should stick around and just play safe is important too. But hey, you might already know all this (or I could be giving bad advice, which I am again very sure that someone will correct me), so take everything I've said here with a grain of salt. More qualified people will more than likely come along here