You'll only alchemize one noted item per spell cast of High or Low Alchemy.
I think you can alch it and get profit.
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.
yew longbows
Where? Anywhere. You might do it right by the Grand Exchange, where you buy stuff that you high alch. Or you might take a few noted items, nature runes, and a fire staff, with you, wherever you go, to do some high alchemy when you are chatting with friends, just waiting for something, etc. - Yes, high alchemy is one of the few things you CAN do with noted items!
Adamant Platebody
A great thing to high alch is a magic longbow. If you can fletch thousands of them and then alch them all, then you will make a ton of money. If you don't have the fletching level to make magic longbows, you can make magic shortbows and yew longbows and high alch those. I wouldn't recommend high alching yew shortbows. Another item that will make much money from high alching is a steel platebody. If you can mass make them, from raw materials, you will not only make tons of money from high alching them, you will also gain smithing and mining experience. Items from the skills above and crafting are great high alch targets. Try to experiment with items with other skills though; you never know that you have a low-priced item that can be high alched for a healthy load of gold. On any high level monster hunting trips, you should bring your nature runes and fire runes/staff also. You never know what drops are going to appear before you. Many steel, mithril, adamant, and rune items are worth high alching. Don't high alch dragon items or better, though. They cost much more in the grand exchange.
No, you still do lose a bit.
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.
no, have to wait til midnight gmt
I can't find any auto alchers, but i found out about sap's autocurse. 3 requirements are locate the spell book, spell then monster (if curseing) or item needing to be alched. Just type in sap's autocurse on google.
No, any item gives the same exp.
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.