Who owns the websites and automations I build for a client, and can I hand them over?

That is your choice as the agency. Many agencies keep ownership of the assets they create (for example the Facebook ads they run) while the client pays a monthly retainer, so if the agreement ends the client cannot keep using them. Others hand everything over.

If you want to hand assets to a client, you can export pretty much everything: download a website as a ZIP file, transfer apps and transfer contacts.

Votel also has contract signing for your agreements: upload a document and drag and drop signing fields onto it, or type or paste your contract text in.