Hello, I can create a joomla component that can calculate a price for petsitting as you described. I have a great deal of experience in joomla reservation systems.
I am able to get the component working in 5 days, styled to fit your site and installed, and I don´t need any milestones - I am happy to get paid when you are happy with my work.
Let me know if you have any questions,
Regards
Ben