Dual monitors, number pad, spreadsheet stamina.
Long sessions in spreadsheets and tax software. You need screen real estate and a chair that respects your lumbar.
Cheapest options with the strongest reviews. Sorted budget → premium.
Frees your entire desk surface and lets you finally put the monitor at eye level. It's not the fanciest arm, but it holds two 27" panels rock-steady for under $60.
The default budget answer. Adjustable arms, breathable mesh back, tilt lock, and a five-year-plus lifespan in most home offices. Not a lumbar throne, but for the price nothing else touches it.
The workhorse second monitor. Nothing exciting, nothing wrong. Buy two, put them on a dual arm, forget about them for five years.
The office mouse other office mice are compared to. Quiet clicks, magnetic scroll wheel, works on almost any surface, and lasts weeks on a charge. There is no better $95 you can spend on your setup.
The correct first mechanical keyboard. 75% layout, hot-swap switches, Mac/Windows toggle, wireless. If you type for a living, this is the smallest upgrade with the biggest daily payoff.
An alternative to one item in the kit above. Not required, but for the the accountant this is where extra dollars actually pay back over years.
The cheapest Herman Miller worth owning. Y-Tower back gives real ergonomic support without the Aeron price tag, and the 12-year warranty means you'll own it longer than your car.
Two 24" panels for accounting work. Snap-to-side is easier and it's cheaper.