Hi, Kate from BookingBug here. We do offer a free plan specifically built for people looking for a free booking plug-in for WordPress. If you’re looking for full, advanced BookingBug functionality however, we would recommend one of our paid plans, details of which can be found at http://www.bookingbug.com/pricing.
Apologies for any confusion, we’ll review the wording on the plug-in info page to make it clear there are both free and paid for options. The link to the free plan can be found towards the bottom of the pricing page above.
If you have any questions, please feel free to get in touch with our support team at firstname.lastname@example.org.