We recommend going with the Magento 2.x version since the Magento 1.x version will stop receiving security updates eventually (there is not an official date for this, could be 1 – 2 years away). Here is a comparison of the two: https://rentalbookingsoftware.com/magento-1-9-2-4-rental-booking-system-vs-magento-2/ Please be aware that there is no easy upgrade path from Magento 1.9.x -> Magento 2.x path you will need to start over again with a fresh store.
Magento Community Edition is a free open source shopping cart, it does not cost anything. Our Rental Booking System is a extension for Magento shopping cart that adds on all the features that are needed for rentals. This gives you many advantages. First you can not only rent products, but also sell them if you want to. Second, Magento has a huge user base so there are lots of other extensions, templates, and developers that can enhance your store.
Our rental booking software runs as a module / extension for Magento. This means that we have extended the core functionality of the Magento E-commerce shopping cart so that it can handle rentals.
There are many other Magento modules / extensions available besides our rental booking software extension. These Magento extensions do things like integrate social networks, payment systems, shipping systems, customer relationship management systems, and many other features that would take too long to list here.