My basics are light tank top, long sleeve top and cardigan to layer for warmth, jeans that can be worn long for a dressy look or cuffed shorter for casual look and a plain dress that can be worn to the beach but dressy enough for a cocktail party with the right accessories.
The next can be dictated by weather and destination.
For hot weather a short skirt for the beach to throw over bathers, sandals for the beach and bar, ballet flats for comfy walking, long tank for sleeping in or slopping around in when things are dirty and a flirty light summer dress for when it gets relay relay hot
For hot weather a knitt pullover for layering, a jacket for a good protective layer to the outside weather, leggings to be worn under skirts or under pants for extra warmth, boots for very extra warm feet in the rain and a wool jumper or cardigan for when you need to be VERY warm.
For cheap 40's vintage (my favorite vintage era) style I love brogues as dressy flats and hard soled dance shoes, high waited shorts to wear on there own or over coloured/patterned tights, flared above the knee skirt with pockets, plimsolls for dancing lindy in on slippery floors and low wedges for the night on the town (never take high heels unless for a specific event because you will never wear them, trust me).
I can dress up any outfit with cool scarfs, vintage jewelry, funky tights and socks but whatever you take with you be ok with yourself if they get lost or damaged on your travels. You don't want to take irreplaceable family heirlooms or expensive vintage favorites but in the end its up to you. When I go to lindy exchanges for dancing I have to take at least 2 to 3 tops for each night of dancing with all the sweaty that will be soaking through from dancing into the wee small hours in the morning night after night.
All images from Cotton On