Variant Homunculi - please check my math and critique

[Mark Hoover]

I've asked for advice in several threads about the costs for adding powers to homunculi; so far I've received no responses. Please see my spoiler below:

Costs to add powers:

0th level: at will = +500 GP
1st level: at will = +1000 GP; Per Day = +200 GP
2nd level: at will = +6000 GP; Per Day = +1200 GP
3rd level: at will = +15,000 GP; Per Day = +3000 GP
4th level: at will = +28,000 GP; Per Day = +5600 GP

All costs figured as follows: a 7th level Universalist Wizard adding a spell at the lowest possible caster level. I used table 15-29: Estimating Magic Item Gold Piece Values; on that table I calculated these based on Spell Effect: Use-activated or continuous. The costs in the spoiler then are already reduced by 1/2 b/cause I have all the appropriate feats and spells to craft these enhanced homunculi myself.

1. did I estimate correctly?
2. if I add powers in this way, do they just work on the homunculus employing them whenever it wants?

Example: I take and craft a base homunculus making no mods other than these powers in the construction. To this thing, during construction I add Light so it can always generate it's own light for the benefit of my human character and also Scorching Ray (a laser) to blast my enemies 1/day. This then adds +1700 GP to the homunculus in special lenses and refractors, crystals, unique alchemical substances etc. correct?

[Mark Hoover]

Please, I have a game on Thursday night. I suck at being a player (I haven't played in years) so I need to make sure I'm doing this right.

[blackbloodtroll]

Have you examined these rules?

Also, you are working with custom magic item guidelines.

So, it is a bit of trial and error, and working with the DM.

There is no hard formula, just a formula for guessing an appropriate price.

[ryric]

If I were your GM I'd be leery of allowing custom spell-like abilities on your homunculus, just for action economy reasons. Also, not all spells of the same level are equal once you start making them potentialy at-will. Honestly if it's been a long time since you played you might go for something a little more cut and dry before tackling something that requires copius houseruling.

Rather than directly giving SLAs to a homunculus, for which AFAIK there are no actual rules, you might look at the modifying constructs material in Ultimate Magic (available free via the PRD).

Edit: blackbloodtroll included a link to that setcion of the PRD in his post. I should have paid closer attention.

[Mark Hoover]

What about trading out the bite attack?

homunculus wrote:

Melee 1 bite +3 (1d4–1 plus poison)
Bite—injury; save Fort DC 13; frequency 1/minute for 60 minutes; effect sleep for 1 minute; cure 1 save. The save DC is Constitution-based and includes a +2 racial bonus.

Obvoiusly I'll have to get final say from my GM, but do you think its feasible to trade out this bite attack for a melee attack that inflicts instead 1d6 Acid damage (Acidic Kiss) requiring an Acid Arrow be added to the monster's creation?