Pioneer offers a refund of the deposit within 15 days of reservation deposit receipt. Full payment is due within 90 days of departure and is non-refundable, as we must pay for hotels and other expenses in advance.
Pioneer Tours and Travel highly recommends travel insurance. Most policies include cancellation at any time. Here is a link to a site with many choices:
*According to the above site, one of the policies, named best for seniors by Forbes, is Tinleg, for about $393 per person for the tour (not including airfare, which you can purchase along with your flight).