For convenience, lets assign names to the two styles of item creation.
- Casual Item Creation: While out adventuring (e.g. killing monsters, disarming traps, murdering folks who don't look like you because they don't look like you, stealing family heirlooms) adventurers do other stuff that's usually unimportant and handled off-screen (e.g. taking care of bodily functions, maintaining weapons and armor, restocking spell component pouches). A creature with an item creation feat who spends a day adventuring uses that off-screen, usually unimportant in-between time to work on items. Between murder sprees the creature finds 4 hours of time to work on stuff, but with that 4 hours it makes only makes 2 hours of progress.
- Dedicated item Creation: If a creature has an item creation feat and access to a "controlled environment [...] where distractions are at a minimum" and it can get to that environment and it can spend at least 4 hours there, it can make 4 hours of progress on its stuff. The DM's determines what constitutes that controlled, distractionless environment.
You don't combine the two. During an adventuring day 2 hours of progress is made on the stuff, or if capable of getting away for at least 4 hours, 4 hours of progress is made on the stuff. A high-level wizard who teleports from the dungeon to his lab or hauls his portable workshop into his mage's mansion and crafts away for 4 hours definitionally isn't out adventuring the whole day--he's spent part of it crafting! He won't get the free 2 hours per day, but he will get the whole 4 hours (barring interruptions).
The idea is to permit PCs who take item creation feats to use those feats even in a fast-moving campaign. If you're the wizard on Team Fighter, for example, the rest of Team Fighter can just keep on going day after day without stopping, and if you want to accompany them on all their adventures, you'll never have time to scribe a scroll. The casual item creation rule let you scribe a scroll despite not having time or facilities available for dedicated item creation, albeit at a vastly slowed rate.
With base price being defined as how much the item is priced in the store, and not the discounted cost for crafting the item.
Correct.
Items you can buy from the store usually have a CL listed.
For example, the Ring of Invisibility has a CL 3rd, so a player would need to take a DC 8 spellcaster check to successfully craft the item.
No, oddly enough. The crafter of the item sets its caster level, from a minimum of whatever it takes to cast the requisite spells (or other requirement listed for the item), to a maximum of the crafter’s own caster level. Since caster level typically costs money, increases DCs, and so on, most crafters use the lowest caster level possible for the item.
The caster level listed with items is the “typical” caster level for that item, where “typical” is more-or-less just something the authors made up. For most items, it is the minimum (e.g. that ring of invisibility, requiring as it does the 2nd-level invisibility spell, which has a minimum caster level of 3rd), but there are exceptions (e.g. sovereign glue, which has an absurd listed CL of 20th, despite only really requiring 3rd for make whole).
From what I can gather, the cost to craft a magical item with multiple abilities costs the full price for the most expensive bonus, then 1.5 times the price of each additional bonus.
Correct.
It is worth noting that D&D 3.5, upon which Pathfinder is based, added a rule in Magic Item Compendium that certain, basic sorts of bonuses do not incur this premium. For instance, making your ring of invisibility also include a deflection bonus to AC (à la ring of protection) would not cost extra (just the cost of ring of invisibility plus the cost of ring of protection), because deflection bonuses to AC were one of the “generic” bonuses you could have on rings. Other examples included enhancement bonuses to ability scores, resistance bonuses to saving throws, etc.
This change allowed for characters to get their critical math fixes, while still allowing them to get “fun” and interesting items. It led to a much smoother game that penalized characters less for being responsible and buying the critical, but boring, +number items.
I will admit that Paizo not only has not ported this rule, but adamantly opposes it with its recommendations. Paizo considers it important that characters pay extra for combining such items. I will state flat-out that they are quite simply wrong. This attitude massively, and unnecessarily, shafts the classes that were already weakest. I cannot more strongly recommend that you ignore them on this issue.
Lets say I want to craft a Ring of Invisibility and also enchant it with Magic Aura so that it registers as a non-magical ring.
Your example is done correctly.
- Does adding the Magic Aura effect to the Ring of Invisibility increase the final Caster Level of the ring, and thus the DC spellcaster check? If so, by how much? Just 1 since I used Caster Level 1 to add the effect, making the ring a CL 4th with a DC 9 spellcaster check?
Caster level requirements are minimums, so use the highest minimum as the overall minimum of the item. In this case, magic aura requires CL 1st and invisibility requires CL 3rd, so the ring requires CL 3rd. You could craft with a higher CL (requiring a higher DC), which would make the ring more resistant to dispel magic et al.
When you upgrade a magical item or add additional abilities to an existing magical item, do you take a DC spellcaster check at the end of the crafting time? The rules do not state this outright and I've not been able to find an answer.
- If you do, do you use the CL of the new ability for the check? With the example for adding Invisibility to a ring of protection, would the DC of the spellcaster check be that of the CL of the ring of Invisibility (3rd), or something else?
The DC would be based on the item’s CL, whatever it is. At a minimum for this ring, 3rd.
Does the CL of the item increase when upgrading an item? Bracers of Armor has a CL 7th regardless of the strength of the enchantment bonus. Would upgrading the bonus from +1 to +3, or +1 to +5, still use a DC 12 spellcaster check?
If you were correct about bracers of armor requiring CL 7th regardless of enhancement bonus, you would be correct. I believe there may be some examples where this would be the case.
However, the bracers of armor do not require CL 7th. Rather, they require that
creator’s caster level must be at least two times that of the bonus placed in the bracers, plus any requirements of the armor special abilities
Best Answer
2000gp/day
The feat only gives a very short description of the item creation rules, and then refers the reader to the actual rules:
The magic item creation rules are authorative and supersede the feat description. The "1 day per 1000 gp" rule is merely a convenient combination of the "8 hours per day", and "1 hour per 1000 gp" rules for the sake of brevity. Since the magic item creation rules state that accelerated crafting reduces the time spent to 4 hours per 1000 gp, but does not touch on the 8 hour daily limit, there is no reason to assume that the daily crafting time limit is suddenly reduced to 4 hours.