huh I always though it was every two levels since you get one at level 1 then 3, guess I'll have to take a flaw.
It is one every 3rd level, the 1st level one is a bonus, like the maximum hit points and the skill points x 4.
I'll just be posting what is relevant right now about enchanted weapons. This is from the magic weapon section of the DMG, but it is a rather heavy read.
To enchant a weapon you must have a masterwork weapon first.
+1 enchantment costs 2,000g. This can only ever be +1 to hit and attack, and it does not stack with masterwork bonuses.
+2 enchantment costs 8,000g. This can be any +1 effect (ie flaming or shocking) in addition to the +1 to attack and damage.
+3 enchantment costs 18,000g. It can have either a +2 effect, or two +1 effects in addition to the +1 attack and damage.
Magic weapons require a +1 enchantment before you can start adding effects. This means that a shocking longsword must be at least +2. They are worth it in the long run, but difficult to start up. And yes these count as magic weapons for overcoming damage reduction.
The +'s mentioned above are the bonus relative to cost, not the bonus to hit and damage. You could think of it as levelling the weapon, but with gold instead of xp. Every starting weapon that wants to grow up into a legendary adventuring tool needs to be considered master-work. Some special materials include master-work in their costs, others you need to spend 300 gold on. Special materials, base weapon costs, and master-work do not count towards levelling your weapon, they are more like the a 1st level adventurer starting with 25 point-buy instead of the crummy stat arrays that most N.P.C.s are stuck with...
Weapon levels cost 2000gp multiplied by the level of the weapon multiplied by itself. A level 1 weapon costs 2000 x1 x1 =2000, level3 =2000 x3 x3 =18000gp.
A weapons first level must always be an enhancement bonus. An enhancement bonus makes the weapon stronger, giving it extra DR and HP. It also grants it a bonus to hit and damage, of the same type as master-work, so they don't stack, but if the weapon's magic is suppressed its master-work bonus is still effective...
For levels after first it can take levels in
other abilities. Many abilities are equivalent to more than one level, so you need to take multiple levels at once to get them. Vorpal, for example, is a +5 ability, so to get a +1 Vorpal weapon you would need to go straight from level 1 to level 6 without using the intervening levels.
Weapons have a maximum level of 10, normally...
You generally cannot take the same ability twice...
Specific weapons, such as shatterspike(a longsword designed to break objects, that forgot to get itself updated to 3.5th edition...) generally require a D.M.'s approval before being further enchanted.
There are a maximum of 5 levels of enhancement bonus, and while +5 enhancement is a pretty good deal for a two-handed weapon, a weapon that you really don't want to see break, someone who has trouble hitting their opponent, or a weapon with an ability such as defending with effects based upon enhancement bonus, there are spells that can grant a temporary enhancement bonus, so people generally assume that they can get that from somewhere, but those spells are, well, spells, so they may not come up in this party...
As for masterwork being wrong, it is a starting point for a magical weapon, it is a cheap way for a low-level character to get a weapon bonus, and considering that a +2 weapon costs 8000, it really isn't much off of the scale...
I completely missed that talented requires focus, I will need to look into rejigging my feats...