Is $20,000 to replace deck with Trex Transcend Lineage a fair price?

We have an approximately 1000 sq ft deck that is old pressure-treated lumber, likely over 10 years old and not well taken care of by the previous owner. I've already replaced one piece of rotting wood and removed planters that trapped water. The boards seem too close together in some parts, which I think leads to rot. The joists seem okay, a little spongy, but have good purchase with a longer screw. I'm debating restoring it versus replacing it. I really like the idea of not doing regular maintenance and also see it as an opportunity to put in proper spacing and repair anything that needs it. It was just one board last year, but another is already starting to get spongy. I'm hoping to avoid a complete tear down, as it seems really just one area is problematic. The deck is north facing and gets a lot of afternoon sun. We are in the New England area with lots of rainy, humid summers and freezing winters.