If you're looking for Jaco vacation villa rentals by owner similar to the style and offerings of 'https://www.jacopartyvillas.com/', you can explore the following approaches:

Local Listings and Directories: Check local directories or listings specific to Jaco or Costa Rica. Sometimes, smaller local websites or directories can provide listings directly from villa owners looking to rent out their properties.

Social Media and Online Groups: Joining Costa Rica or Jaco-focused groups on platforms like Facebook can connect you with owners who advertise their villas for rent. These groups often provide a more personal touch and direct interaction with owners.

Property Management Websites: Some villa owners may list their properties on property management websites that specialize in vacation rentals in Costa Rica. These websites often feature a range of properties, including those managed directly by owners.