Hi Snoekie,
1- Yes, until you get the Artifact skill, shops are the only way to get your inventory IDed.
2- Don't spend money IDing all items. Check to make sure you got more than one. If not, don't ID it. Once you ID one, all the others that your character is carrying at that time will also be ID.
3- Money: ***Spoiler*** go talk to Gorthius, he's the thief on the South Eastern side of Valeia, ask him about H'Thark. He'll give you some lockpick. Reload until you get 3. Go sell them (you can keep one if you want). That's gonna give you 2250 gp (1500 if you keep one)
4- Save for guild membership. You can get all your equipment on the go. The great advantage of ID is that once you ID, it sells for usually 2x as much. Since to ID it you need the base selling price of the item, ID become productive if you have 2 or more of the same object.
5- Wish I knew... I could retire early, buy a small plane and do mercy flights for people in need of medical services