Re/code: Two little-known online marketplace startups, OfferUp and VarageSale, have secretly raised money from two of the biggest names in venture capital — Andreessen Horowitz and Sequoia Capital — and they’ve been trying to stay under the radar as they go head to head in building what they hope will be Craigslist killers. OfferUp, based in Seattle, and VarageSale, based in Toronto, both make mobile apps that people use to quickly buy and sell stuff from other people who live in their towns.