Isn't constant real time tracking of all player gil transactions to make certain the player retains the required amount to purchase the house in addition to the amount needed for whatever transaction they're trying to engage in then automatically cancelling the player's entry if they fall below that amount unrealistic when the game can simply put a hold on the player's gil by requiring the entry fee to be paid in advance?

If the players is entering into multiple lotteries, does the game track the cumulative amount of all purchase prices for the lotteries entered or does the game only track the highest value? If only tracking the highest value, will the game still recognize the other entries the player had as valid or will it treat the players as if they had only entered in the one?

When does game decide to hold the drawing for the lottery so the house actually gets sold? Is the drawing held on a hidden random timer if there's not going to be a stated period for players to enter?

How do those who entered find out when a winner was chosen? Are they supposed to keep going back to the house and checking the placard?

If the drawing is held and the winner is offline, is the game able to deduct the gil from the offline character or does it have to wait for the character to be online to deduct it? Could it even assign the owner to the house if the character is offline when the drawing is held?

Until we know how a system works and what the rules are, we can't answer how to troll it. Trolling the system comes from manipulating loopholes in it and any flaws in the underlying programming. Online multi-player games are filled with examples of players who chose to exploit systems not only for personal benefit but sometimes just to disrupt the game experience of other players for their own amusement because they did things not anticipated by the developers.

But as you said in your initial reply, SE isn't looking for us to design things for them so none of this matters. They know players are unhappy with the current housing purchase system. They know some players want a lottery and others are against it. They have their own ideas of what they want the purchase system to be. We have to wait and see what they choose to do to address the situation.