Is sanding sealer required?

I’m in a bit of a pickle, I want a kit, but I don’t want to pay $100 on finish. So, I’ve been trying to cut cost everywhere I can and still get a good result. Can I do without a sanding sealer? If not, what is the cheapest way I can pull-off a satin white finish?

It's less about the 'sanding' bit and more about the 'sealer'. It does help stop the finish sinking into the wood. So you spend a bit more on getting the sealer or you spend some more on paint as you'll need more coats if you want a flat surface finish.

Its hard to save much money on a given finish, because if there were shortcuts for a given finish people would take them. The cheapest way to finish a guitar is probably going to be natural with grain showing. My Build No 2 (see sig) has two or three coats of thinned polyurethane varnish, semi matt, with no grain filling at all, and to my mind it has a pleasant enough vintage feel. Look at it cross light though and there are thousands, maybe millions of little pits with the grain pores. That's cool because they match the wood, and maybe even add to the grain effect, but if I did the same thing with a painted guitar it would look like hell, because every damned pit in the grain would show up, especially in bright light. It would look as if someone had sprinkled sand on the paint.

So if you're heading for a satin white finish something has got to fill all the pores and its going to be money and work. You need an initial coat(s) that is thick enough to fill all the pores and be rubbed down flat, sanding sealer, filler/primer, something has to do that job. But the good news is that if you get that initial layer really flat and fill all the pores you won't need nearly so many layers of top coat. And typically top coat is more expensive.

Thanks guys!