Q. Do things like the furnace, glory hole, and annealer have standardized sizes or are there different sizes for small studios?

Artists working in small studios have developed a variety of equipment that suits their way of work.

The furnace, glory hole, and annealer have do not have standardized sizes. A glassblower will want a larger capacity furnace if they create big pieces that require many gathers of glass. In that case, the glory hole doors must have an opening large enough to insert blowpipe with its molten glass for re-warming. The doors may be designed in three sections: a small opening to conserve heat while the piece is being started; a larger opening to accommodate the piece as it is being shaped; and a wide opening to keep the piece hot as it is being finished. The doors may or may not have an automatic opener.

Likewise, the annealer fits the size of the piece -- or the quantity of pieces made in a blowing session (many Christmas ornaments require a fair amount of space.
Annealers may have a door at the top of a box; on the side; or the walls and ceiling of the box may rise to reveal the floor of the kiln/annealer.

There are lots and lots of variations.