Affordable Tours is a United States travel agency, with a mission statement to provide high-quality trips at low prices. They obtain discounted prices from operators because of high sales volumes. Affordable Tours features a search page where you can sort their European packages by price, giving you the cheapest options first (see Resources).
In 2010, Go-Today featured a few holiday packages to Europe for between $800 and $1300. Among their best sellers were air and land packages to Paris or Barcelona, both for $799 per person. Go-Today's packages, however, do not include U.S. customs fees, airport taxes, extra baggage fees or security fees. See Resources for a link to their site.
According to Expedia, their customers saved up to $450 per trip to Europe on discounts acquired by booking their air tickets and hotels together. The site features quite a few special deals, with airfare and accommodation combinations for under a $1000. You can also include a rental car in your package.
