I am in the process of renting a lot of points.....and I feel like I'm going against the grain by not offering long payment plans. But honestly I'm not a credit card company. If I put the reservation in their name I lose the use of the points and I want full payment. If it's not their cup of tea they can go elsewhere....and they have.
The folks that I've made reservations for and who have paid upfront are great, are grateful and "get it". So I agree with the "set the expectations" rule and don't worry if they don't want your terms. Find someone else. If you've been burned......ask for full payment by paypal. You have to absorb a small transaction fee, but you can transfer the payment into your bank account as soon as you get notification.
That's how it's done on ebay...you make a purchase...you have to make payment based on seller's rules. You don't want to follow them....then the seller moves on. It took me about 2 hours to get over the guilt of not accepting their terms........