It doesn't matter where you alch, just alch anywhere:
If you want something to watch whilst you alch: Go Castle wars or a place like that.
If you want peace and quiet: Go to a place like Mos' Le Harmless, or the elven place, where not many people have access to.
If you want someone to talk to, visit a friend or go to a POH and do your alching.
yew longbows
Adamant Platebody
No, you still do lose a bit.
I recommend high alching items like maple longbows (u) or yew longbows because when you alch them they gives you more coins than if you sold them.
To be honest with you, you shouldn't really lo-alch anything since it would be a waste of runes or/and cash spent on those runes, unless you make platebodies steel+ yourself, then low alch them.
go to the highest floor in the wizardtower and there is a lesser demon, you can kill... (good place 4 ranging 2 I guess) If you are 21 you can begin with money making for low alch (you'll get alot of loss) low alch till you are 55 and then you just high alch till 99 (you'll gain a bit loss)
I think you can alch it and get profit.
no, have to wait til midnight gmt
Well, there are lots of good things to alch, however, they constantly change daily so it is hard to find a proper thing to alch.Check out alchprices.com , they will show the things to alch with no loss.
No, any item gives the same exp.
Level 56 would be good and you can alch adamant platebodies for a profit.
You cannot alch a Dungeoneering item.