Members can have both Owner and Sitter accounts using the same email address. To create the second account a member should register for the other account using the appropriate registration form.
When completed, the type of account they are logged into will be noted under their member name. To change accounts a member needs to click their name and choose the other account.
Members that already have both owner and sitter accounts (but with different email addresses) can link their accounts by changing their email address on both accounts to their preferred email address.