I have seen many first class restorations as well as cars equipped as this 31 listed on ebay and elsewhere for less money than the current bid, go unsold. Lets hope this is an indication of general increase in Model A values. But I'm not holding my breath.
More to the point, ...how many cars have you seen sell directly thru eBay? From my experience, very, VERY few do. These days, a Buyer travels to view the car in-person and a sales deal is generally made outside of eBay. Most Sellers never report the sale to eBay, -so using sold sales as a benchmark is not very accurate.
To the other comments regarding seeing cars sell for less, ...this is one of the most difficult things for any looker or potential buyer to understand. You can place two restored Model-As side-by-side, and there can be $20k difference in costs to make them truly equal. They both can look equally pretty but one will stop well and the other one won't, -one will run well and one will be low on compression. The same can be said for good vs. bad steering, transmission & rear end noises, and the like. Matter of fact, one can have a rusted gas tank and still look very pretty on the outside. My point is, wouldn't it be a fair statement to say that you guys making these 'arm chair appraisals' really have no idea of what something is worth unless YOU can physically inspect and drive the car enough to make a proper evaluation to know everything there is about the car?
As to the vehicle in the eBay listing, the above applies. Having a very well respected name in the street rod industry to be the advisor for such a vehicle in the restoration world is not always the most prudent thing if someone is looking for authenticity however without a thorough inspection of this vehicle, you just never know. Oh, and yes the costs for nicely restored Model-A vehicles ARE going up. The costs for parts & labor have risen and so it is about perceived value. If a novice hobbyist purchases a 'poorly restored' Model-A Roadster for $15k that does not Start, Stop, & Steer well, -and then must have those deficiencies professionally repaired, it is easy for them to spend an additional $20k or more having the vehicle repaired/restored to a reliable & safe condition. At that time, spending $30k for a higher quality vehicle is the better value in most novices eyes.