I agree that these topics could/ should be better signposted on the main web page.
The majority of THS members aren’t on the forum but will have the same questions and issues that are discussed here .
This is From the Help section - if you 
"cameras“ this comes up
According to THS the sitter pays upfront !! But most sitters make it clear to hosts before a sit is confirmed that they do not agree to this term .
https://forum.trustedhousesitters.com/t/sitter-has-to-pay-veterinary-expenses-up-front
The Third party policy is here
https://support.trustedhousesitters.com/hc/en-gb/articles/360001881117-Third-party-policy