This is organization dependent, but I've run into multiple orgs that will approve a mid-level manager up to $5K/mo in recurring or a single expensive of $20K.

Exploring the CC path, there are spending limits often imposed that may not even match their spending parameters. For example, the CC may have a daily max of $5K. I've personally encountered scenarios where we have to bill the CC in consecutive days (with their approval) to stay under the spending limit.

Last, many orgs are starting to impose tighter restrictions on recurring expenses - so be aware of that. You can create one time charges around activation / implementation / customization / training / data migration / etc that will help you increase your revenue for that customer without having to bake in so much on the recur fee.

Think of it like Shipping & Handling... its an after thought for a lot of people after they decide the core product is worth the price you outlined.