To me 1000 sq feet for 2 bedrooms sounds fantastic. So many ways you can use that space creatively. So many different layout options and shapes.
My recommendation would be to start with an architect. Given a good budget and defined parameters you should get something really good. And (at least here, don't know about there) architects like to be project manager as well to make sure their baby is executed well.
[1] starter apartments here can be under 200 sq feet. Not sure who wants that (they are typically quite expensive) but someone is buying them.
Home costs do not scale proportionately with their square footage. For example you still have one refrigerator in most homes regardless of size, one front door, pay base flat fees for services and trades just to show up, permitting fees, etc.
The only marginal financial cost will be energy required to heat and cool the space. Seeing as the original commenter is in the SeaTac area, with a temperate climate, one would think total energy costs tend to be low (I do not live there so I could be wrong).
It’s not that there aren’t any options that size, I happily spend the first decade of my adult life in residences that size, but dwellings that size are almost exclusively condos/apartments in the US. Others have noted some good reasons for that.
Building form scratch with an architect in America is also very, very expensive. I know folks that have gone down that route and it easily doubled the final cost of their home. What could have been a 250k property cost over 500k when all was said and done. It's just not common to see done unless you are wealthy.