Here’s a tip from Mike:

“We are constantly looking for the right tools for detailing and weathering. Check out the cosmetics counters in big stores. There are several unique shaped Q-Tips that are perfect for applying paints and chalks and are reasonably priced for large quantities that can last forever. Shaped sponges for Bathing and Complexion Care and are super handy for paint application and clean up. Look around the counter – you never know what could be useful.”

Even some of the discount stores have cosmetic sections with some really useful brushes etc ideal for model train weathering.