Caster levels for crafting

[Wu Li]

This is my first post so please bear with me if I'm going over old ground here.
I'm a fairly new player who's joined a well established group and I don't understand the way they are applying the rules for adding special abilities to arms/armour. The bit I'm having trouble with is the crafter's caster level.
Rules state 'For an item with only an enhancement bonus, the caster level is three times the enhancement bonus. If an item has both an enhancement bonus and a special ability, the higher of the two caster level requirements must be met.'
If I want to add Brawling to my masterwork armour, the Brawling ability has CL5, costs +1 bonus, and I need to add a +1 enhancement bonus in order to add the special ability. I understand this to mean that the +1 enhancement bonus requires CL3 and the Brawling is CL5, so I need to be the higher of the two, i.e. CL5 (I get that I'd have to be CL5 anyway in order to take the Craft Arms/Armour feat)
My group is interpreting the rules differently, adding the +1 cost bonus for the special ability to the +1 enhancement bonus, making the armour effectively +2, which gives a minimum caster level of 6.
Their argument seems to be that if you take it to extremes and stack multiple abilities onto a single item, you could end up with a fairly powerful item potentially created by a relatively low level caster. My feeling is that the cost in both time and money balances this out - a low level character is not likely to have the funds.
Another question comes to mind - if my armour already has a +2 enhancement bonus and I want to add Brawling, do I need to count the CL for the existing enhancement bonus, or is that only relevant if I am actually adding the +2 myself?
I understand that each group can create their own house rules, and if this is the way they have decided to work it then I am happy to accept it, but I would like to know what the general consensus is.
Sorry if this is a bit long winded, I just wanted to be clear.

[Ipslore the Red]

You don't need CL, technically. You can ignore any requirement other than the crafting feat by adding 5 to the DC.

[Reyzoul Soulstorm]

I agree this is an interesting question that after much research, I am still unclear on.

So yes I know I can ignore the CL requirement if I want to by raising the DC by 5.. but that does't answer the problem of.. just what CL is actually required by the creator?

I have two theories

Option1) consider each enhancement separately?
+1 enhancement is 1*3 so CL3
brawling is +1 effective so 1*3=CL3
doing both at once or in sequence.. max of the two is still CL3?

Option2) do they stack? (I favor this method, but I can't find clarity in the rules)
to put on the first enhancement, the creator CL requirement is 1*3=CL3
But when adding the second enhancement (Brawling), because it is an enhancement equivalent, now the armor is effectively a +2 so so the CL requirement during that phase or if done together is 2*3=CL6.

[note that not all armor enhancements are enhancement equivalents, if the second enhancement was lets say.. energy resistance, that seems to be just a straight up gold expenditure, the effective enhancement of the armor doesn't seem to change.. so the required creator CL level in that case would still be 1*3=CL3?]

How does this work?

And WuLi.. as for the CL5 on the brawling enhancement, that is not the required caster level to craft it, but instead that is the caster level of the enhancement.. Ok that sounded confusing.. But I think this gives clarity... It is the basis for the DC target to craft that enhancement (but not a basis for the caster level of the creator).. and also the caster level used if it is affected by a dispel magic. The CL and the construction requirements are clearly separated in the PRD.

http://paizo.com/pathfinderRPG/prd/ultimateEquipment/magicArmsAndArmor/armo rSpecialAbilities.html#_brawling