Upgrading Weapons - What's the math?

[Silverghost]

Referring to Pathfinder RPG rules and the examples on this page.
http://paizo.com/pathfinderRPG/prd/ultimateCampaign/campaignSystems/magicIt emCreation.html

Q1: Is adding an effect to a magical +1 weapon considered adding differing abilities for the x1.5 purpose? Do weapons only use the (Bonus^2)*2000 rule?

Q1a: How does the math work?
(My assumption is #1 and that the (x1.5 is for other non-weapon items)

Example: Going from a +2 Magic Dagger to a +2 Wounding Dagger
Wounding is a +2 bonus

3 example scenarios:

(Scenario 1)Bonus^2 rule
Wounding = 2, +2 Magic = 2, End result is Bonus 4

Bonus 4 cost) - (Bonus 2 cost), (4^2)*2000 - (2^2)*2000,
32000-8000 = 24000gp?

(Scenario 2)x1.5 rule
Wounding =2, cost = 8000, multiply by 1.5, add to +2 Magic

(Bonus 2 cost)*1.5 + (Bonus 2 cost), ((2^2)*2000) + (2^2)*2000,
8000*1.5 + 8000 = 20000gp? (Surely not this one since it's lower cost)

(Scenario 3) x1.5 rule on the "upgrade bonus"
Wounding = 2 (x1.5) so 3, add to +2 Magic cost

(Bonus (2*1.5) cost)+ (Bonus 2 cost),((3^2)*2000) + (2^2)*2000,
18000+8000 = 26000gp?

Q2: How about if we add another different bonus like Speed (Bonus 3)?
(Same thing I'd assume if it's just the flat Bonus^2 rule)

Q3: What about for upgrading a special weapon like Bloodthirsty Dagger? (I know this is not allowed for PFS play, but I'm more wondering for just the RPG rules if the GM does allow for upgrading special weapons how you guys normally would do it in your campaigns as DMs)

(2 example scenarios]
(Scenario 1)
Would you and the DM just agree on what the flat cost is for that special weapon's effect and add it to the end result of the upgrade?

Example:
Upgrading Bloodthirsty Dagger to a Flaming Bloodthirsty Dagger.
(Default is a +2 dagger of wounding and the bloodthirsty effect)

That would be +2 flaming dagger of wounding + bloodthirsty effect cost.

Calculate Cost of Bloodthirsty Effect:

Assuming Bonus^2 rule is the right way to do magic weapons...
60,802 (Cost of a bloodthirsty dagger) - 32000 (Cost of a weapon with +4 bonus total) - 300 for Masterwork - 2 for dagger =

28,500 Bloodthirsty Effect

Calculate Final Cost:

Which is cost of a (+5 bonus weapon) + Bloodthirsty Effect Cost.
50000 + 28500 + 302 = 78802 Total cost
Then 78802 - 60802 =

18000 Final Cost

(Scenario 2)
Jump to the next bonus value tier above the "special weapon cost" then add the upgrade normally?

Example:
Upgrading Bloodthirsty Dagger to a Flaming Bloodthirsty Dagger.
Default is a +2 dagger of wounding and the bloodthirsty effect)

Find the Equivalent Bonus Tier of the Special Weapon:

60,802gp is more than a +5 Bonus @ 50000gp, but less than a +6 bonus @72,000gp So we round up to a +6 Bonus.

Bloodthirsty Dagger (normal) = +6 Bonus Weapon

Flaming Bloodthirsty Dagger = +7 Bonus Weapon (Because Flaming adds +1 Bonus)

Calculate Final Cost:

End Result Cost - Special Weapon Cost, 7^2*2000 - 60,802,
98802 - 60802 =

38000gp Final Cost

[blahpers]

It's actually very simple.

1. Calculate the price/cost of the initial weapon.
2. Calculate the price/cost of the final weapon.
3. Subtract 1 from 2.
4. Pay 3.

Essentially, it doesn't matter how many intermediate steps you went through to reach a +1 flaming bloodthirsty dagger--the final amount you paid for it should be the same. Keeps things simple.

The 1.5x rule is for combining different magic items into a single slot. For example, a +1 dagger that also acted as a wayfinder would add 1.5 times the price/cost of a wayfinder to the price/cost of a +1 dagger. Weapons with multiple enhancements do not use this rule--they use the rules detailed under Magic Weapons.

[BigDTBone]

The upgrade effects stack directly onto the existing enhancements.

For the +2 dagger upgrade to +2 wounding dagger, you are going from a +2 weapon to a +4 equivalent dagger. The upgrade cost is the difference (32,000-8000) of 24,000gp.

Same for adding speed to a +2. It would be 50,000-8000=42,000gp to upgrade.

For adding to a special item you don't figure out the special properties that aren't given as part of the magic weapon creation tables. You know it is a +2 wounding and you want to add flaming, so you go from +4 to +5 and the cost is 50,000-32,000=18,000gp to upgrade.

[Silverghost]

Thanks for the info guys that really cleared it all up for me.
I had some issue with posting yesterday so I couldn't say thanks then.