I pay a preparer (a single digit multiple of your figure) to file our every year, but we have gift tax filings, kiddie tax computation/returns, RSUs, NQSOs, PSUs, DW is self-employed with employee and employer 401K contributions, wash sales, 20+ pages and 6 figures of schedule D capital gains in a typical year, sometimes some wash sales, etc.
I self-prepared for years and feel I know the tax code pretty well. The first year I went to the EA for tax prep (had a particularly complicated situation I just wanted help on that one item), he asked for my last 3 years' returns so he could check them over. I handed them over, 100% confident that I'd done things correctly. In 15 minutes he spotted an error that we were able to amend for a low-five-figure sum. That paid his fees for about a decade and I've never looked back.
In your case, if you're sure you're doing the RSUs and ESPP basis calculation right, and you can reproduce 2016, then consider doing it yourself. If you have doubts about either of those things, I'd continue to use your preparer, especially if they handle the throughout the year correspondence with the feds as needed.
