A pair of well fitting, flattering dark jeans. No holes, no rips. A bootcut has a more formal look, and a skinny jean with a more casual vibe. But style should always be chosen by what flatters you the most and what you feel the most confident in.
A pair of flattering black dress pants.
A well-fitting jacket. A neutral color you can grab and go, that will work with EVERYTHING. Tailor, tailor, tailor to get the right look on you.
A pair of black and a pair of nude shoes or booties. For best flattery impact, make the toe at least somewhat pointy – a round toe does not elevate an outfit – and choose one with even the tiniest kitten heel. A heel elevates the body differently and makes you stand and walk taller!
A long + a short necklace in gold and in silver.
The handbag. Have one neutral color you can wear with everything.
These basics must be in good condition, no snags, no pilling, no scuffs. Replace them otherwise.