Simple property booking an availability plugin. Works out the box for one property. Add your own little file from the sample for more properties.
Add guest details, booking and payment status. NOTE there is a version 1.3 available but wp is not showing it as latest for unknown reason. https://downloads.wordpress.org/plugin/amr-clearskys-availability-modification-for-27.1.3.zip
This is a mod of the original Clearskys Property Availability calendar which appears to no longer exist.
This version was initially modified for 2.7.1 with wordpress in own directory, shortcodes, multiple properties (rudimentary).
I have done a simple update, removing deprecated calls and notices.
It could use a property add module (that was in clearskys 'paid' version I think),
so has a rudimentary method to add the properties if you need more than one.
For more than 1 property, copy the amr_props_sample.php to amr_props.php, add/deletes line as indicated!
It has now been slightly refreshed for wordpress 4.3 beta - minor changes.