Well, here's the deal (and probably more info then you'll ever want but here goes). They want you to pay with a check precisely
because you can't challenge that $200 non-refundable fee, and to protect themselves against CC fraud on the vacation balance. If you paid with a CC you could cause a chargeback to them and recover the money if you won a challenge over an issue, or the fact that you challenge it at all can cause a chargeback depending on your CC company - so that chargeback (taking the money back from them) is exactly what MV doesn't want. I think they must be processing the check as payable to MV (would that be correct?) and then paying Disney (or whatever other vendor) out of their business account.
While I sympathize with the fact that they've probably had an issue with fraud/other problems (as an internet agency, think of all the people that contact them - mostly good and I suspect some bad) - - and so initiated this policy - that doesn't help you out any. I can also sympathize with the fact that they've done work on your behalf and the $200 non-ref deposit can pay for that time, still that is to their benefit and not yours. They could get out of the liability by taking your CC number and making the payment directly to Disney or whatever vendor they are using, and not passing it though their business acount AT ALL, but I suspect they may be adding some to the cost for their work (that $200?) and they can't charge that to Disney/vendor and then collect it back. So instead of being upfront about a service charge and charging the service charge on the card to MV, and the vacation payment to Disney/vendor - they are doing what I described above. It's actually not unusual in the travel industry, although I prefer the upfront approach. I hope I'm explaining this where it makes sense (I'm in the travel industry so I might assume it makes more sense than it possibly does to the consumer). If they are having you make payment to Disney/vendor direct, I see no benefit or reason for insisting on a check,(but hey we really can't know for sure what their reasons are as I don't work for MV) . If they aren't adding a service fee, I see no reason to not pay Disney/vendor directly, don't know what benefit they'd get by passing it though their business account. It isn't going to sit there long to benefit much from interest, although I guess you'd get a few days, as it's got to get to Disney/vendor quickly.
Not sure how they could be the cheapest on WL either as the price is set by Disney, not MV, and it looks like they maybe added a bit to it? You should make sure you are comparing apples to apples when pricing, itemize exactly what each quote includes. Perhaps some added
travel insurance and MV didn't? Make sure you know!
This is conjecture on my part but it seems to be what might be happening. I'm not saying MV is bad, just that they are protecting themselves by their policy. Whether you want to accept their policy is up to you but you might want to check around about that price. You really will have no recourse about the non-refundable part but if it's the deal you want - does it matter? Is there a big chance you might have to cancel? Are they $200 cheaper than the rest? Worth the risk? On the other hand, cheapest is not always the best - what about things like this policy, their customer service, knowlege of Disney, helpfulness, ease of contacting them, etc? Lots to think about and for you to decide . . .
Good luck with it and have fun. The WL is gorgeous and one of my personal favorites - and I haven't even seen it at Xmas time!
BTW, they are requiring I think, payment 60 days in advance so they have time for your check to clear their account and then turn around and make payment to Disney/vendor by 45 days out.