Hey Primal,
That's fantastic!!!!! I think it's great, the more painters...the merrier I say!
-I heard things like...washing the kit with soap. (is this right?)
Yes, always wash a kit first. Typically, when a resin kit is cast, a mold release is used onto the silicone mold before the resin is poured in. This mold release (many times) has an oil that makes primer/paint not bond well to the surface. Washing the kit in any degreasing soap (Dawn dish soap, orange clean, etc...) will remove this release and help get the piece ready for paint
-Fixing the imperfections, such as filling in holes (with what material I dont know)
Puttying seams/joints, and airbubbles/pin holes is standard. I use AVES Apoxie Sculpt for this type of work, very easy to use.
http://www.avesstudio.com/
-Using a primer before painting. Is this really necessary? If so, what kind?
Yes, primer is needed before painting any raw resin, styrene, or vinyl kit. Basically, primer is made to "bite" onto the surface and give your paint some "tooth" so that is will stick and stay. I prefer Duplicolor Light Grey "Filler" primer myself. Dries fast, sands easy, and covers nice and thin and flat.
-What kind of paint can I use? I dont plan on using airbrush. Just an old school brush so what paints would you recommend? Brand?
Any water based paint will work. But I do recommend that if you are hand brushing, pick up Floetrol. Floetrol is a latex based paint conditioner (you can find this product at any home improvement or paint store) that will work with any water based paint. It will extend your "wetlife" and allow for a better, smoother more professional finish and avoid those ugly nasty brush marks.
- Once the paint's applied & dried up...the paint has to be sealed? I heard of Dullcoat along the way. Is this what's used to not give it a shiny coat? And is this the same as a sealant?
I use Testors Dullcote and a flat finish sealer. Great stuff and can be found at any hobby store.
I hope this helps!