I do agree with the posters above: the grader's comments in all AOPS classes that DS took were of very high quality and useful for DS. (Those were non-geometry courses and there was one so-called "writing" homework problem each week which was manually graded, with detailed comments.)

It may be difficult to find a "good local support" of the same quality.

(I was too brief in my post above. ColinsMum has much more details, specifically re. the geometry class.)