Is Housesitting Or Petsitting Working? [closed]

I have registered with the company at www.trustedhousesitters.com . I could in the future either be doing house sitting or pet sitting or both, at people's homes. Often, the locations are in various foreign countries to mine.

My question is: Is doing the above classed as doing work? Or in other terms, for foreign sittings, and if applicable, would someone have to obtain a work visa or permit to do it alone? Presuming that no monies are usually exchanged between the householders and the sitter as is often the case. Hosts usually give sitters some tasks to do.

Clarifications on this will be helpful, and which countries have any known specific rules too. Thanks.