Here is why using Priceline can cost you $$. I used the site recently for an Express Deal in San Juan. Buried in the fine print apparently it states there could be additional mandatory hotel fees. So if there are two hotels - $150 for one and $200 for the other - there is no way to determine which one will actually cost more - because the fees could be dramatically different. In the end - Priceline is NOT telling you what your final cost will be - meanwhile other hotel websites like Hotels.com and Expedia.com include those mandatory fees in the final price before purchase. It turns out a 2016 lawsuit Singer Vs Priceline ruled on this exact situation in Priceline's favor. Sad. Stick it to the consumer.