I will personally mainly talk from a breeder standpoint in this game and give feedback on methods or concerns I saw in other games that I liked/not liked and what I want to be implemented, if possible. As such, I divided the auction house into sections and I will give ideas and examples based on what I saw, used, or heard about. Once again, this is simply my opinion and I'm fully aware the decision is up to the devs. I feel like this disclaimer was needed, haha! ^^
Temtem Auction House Sections:
1. Space limitations
2. Tax %
3. Time
4. Search functions
5. Selling/Buying methods
Optionable: Cash Shop Bonuses, Seller Reviews
1. Space Limitations:
Ok, first is first, there was always controversy when it comes to how many items, at once, we're able to sell in the auction house. Many MMOs simply have a low amount of space locked, usually, under the paywall. A simple example of this is the Premium/Vip bonuses that we can buy for a monthly/weekly subscription which usually provide us with a lower tax and more space. We are already aware Crema stated they wanna avoid p2w as much as possible, which I think is a very good mindset, but at the same time, we know they face issues when it comes to the amount of storage they can provide us with. The auction space could be an intermediary solution for this problem since most of our items will be on the market and no longer stagnating inside the storage. If later on there's the option to add extra space via the battle pass or whatnot, then we should think we hit 2 birds with one stone: we get the extra space, while they get the funds to make that possible.
A question will be if the auction house will give us the options to sell bulk temtems? Like the ones, we need for breeding a perfect, the 50 SV temtems or freetem fodder. Those are some concerns I gathered from other people. I'm not sure exactly how the space problem works, this is why I don't wanna make unreasonable requests, maybe unlimited space is too much to ask for, since it may be impossible for all I know, but a reasonable amount should be provided. Not sure exactly what a good number may be, but I think between 10-100 or around there, should make any kind of trades possible. with the exception of bulk sales. Those will probably need more information if they are ever gonna be added.
2. Tax %:
I know taxation is important for the pansuns to sink in the trading category. While I understand the importance I don't understand in totality how it works and on what scale it influences the things, as such, I should not speak about things I do not know about. Some of us are already used to player-made auctions, where the seller participants are taxed with a commission, ranged usually from 10% to 5% per item, so if it is anywhere in that range I don't think it will be a problem.
3. Time:
The time context here is simply how long an item will be present at the auction. A basic format will be 1 day/3 days/1 week options as most games do, but in some instances, I saw them having the unlimited option. Simply having an item on the auction until it sells or the seller removes it. I won't mind bigger time periods, but in case those could cause any problems they could be limited by the number of items that can stay at x period of time. Ex: There's 5 spaces that you can use on unlimited time items.
4. Search functions:
As the previous people on this topic already stated, we do require a good search function for the auction house, a bit similar to what people are used with the trading hub in discord. We should have options dedicated to perfects, lumas, eggs, items with subcategories on those, if possible, and, of course, a searching option in general. People in discord are very used to mark the tems to symbolize if they have egg move, if they are fertless or not, even the trait of the eggs or perfects is marked by a symbol. I'm not sure if those marks are possible inside the trading house, but a tag option of some sort will be good to have. In case those are not possible I suggest an item description so we can say all the details related to the tem/item. I also wanna add that all items should have a preview option, from the temtems to the items like simple dyes.
5. Selling/Buying methods:
Selling and buying sound simple enough, but the players are used to 3 main methods for those: buy-outs, offers/negotiations, and of course the bidding on an auction.
Selling/buying should be 2 separate ways inside the auction house. The first one is the basic menu where you see the searched items and each of them provides you with the options to either directly buy the item for the price the seller is asking, or give them an offer which is usually a lower price. (Saw this in a popular MMORPG called TERA when I played a few years ago.) I'm not sure if a similar option, but offering a higher price will benefit since this could be potentially be abused using multiple accounts or used for RMT. (Ex: In metin2 a good way of RMT is making a shop with an insignificant item that has an absurd price. Those who bought in-game currency with real money used those kinds of methods to get their in-game money without being detected. This could also issue that we need some kind of taxation to avoid those kinds of trades) The second way is the auction-like mode. I'm gonna talk a bit about what I saw in a browser game called Howrse. As I stated in the beginning, those 2 ways of selling/buying are separate menus to simple make things clear and easy to find. How they handle it is you, firstly, need to reach several days to be able to participate in those kinds of trades, here, honestly, I don't think is necessary. We shouldn't be limited to use any kind of in-game parts, except for gameplay progression, where once you unlocked the house you should be able to use it at its full capacity. As for items that are inside the auction mode, everyone should be able to post items in it. From what I remember the items were sold in order, you, of course, could have bid on an item that's like 3 days away from being auctioned, but the option to bid was available on every item. It will have a minimum increment, for temtem we could use 100-1000 pansuns and the last who bids take it. I suggest the number of items that can be auctioned to be limited by the amount you can place at once and the time to be bid. As for the order they came for the bid should be in the order they were placed. Ex: I see 3 perfect temtems in the auction queue, I add 2 more items, then another player adds another one, then I add my last so the order is like this: first item is one of the previous existent 3 perfects, then my first 2 I added, then the second person, and last is the last item I listed. Long queues may be a problem, depending on how this will be handled, but space and time limit should ease the problem a bit.
Hope I made my ideas somehow easy to understand and I know it's a big wall text, my apologies for that. I also wanna add that whatever the final product will be, it will be a very important addition to us and I'm, personally, very excited about it!