What is the return policy for iPad Pro purchases?

If you bought it from Apple, no; sell it to someone else. Otherwise, check the store's policy.

(259411)

If you have purchased your iPad directly from Apple, in most countries/regions you have a generous 14-days within which you can unconditionally return an undamaged item for exchange or refund.

In exceptional circumstances, Store Managers might be able to offer some latitude - but this is entirely at their discretion.