A small plot costs 4 mil, player A buys it from the game. Player A sells it to B for 4 mil and B has to also buy the plot from the game for 4 mil. Player B sells it to C for 8 mil and C has to also buy the plot from the game for 4 mil. Player C sells it to D for 12 mil and D has to also buy the plot from the game for 4 mil. Player D sells it to E for 16 mil and E has to also buy the plot from the game for 4 mil. Player E sells it to F for 20 mil and F has to also buy the plot from the game for 4 mil. Player F sells it to G for 24 mil and G has to also buy the plot from the game for 4 mil. Player G sells it to H for 28 mil and H has to also buy the plot from the game for 4 mil. Player H sells it to I for 32 mil and I has to also buy the plot from the game for 4 mil. Player I sells it to J for 36 mil and J has to also buy the plot from the game for 4 mil. Player J sells it to K for 40 mil and K has to also buy the plot from the game for 4 mil. Player K sells it to L for 44 mil and L has to also buy the plot from the game for 4 mil. Player L sells it to M for 48 mil and M has to also buy the plot from the game for 4 mil. . . . . . . . Player S sells it to T for 76 mil and T has to also buy the plot from the game for 4 mil. . . . .
At which point does the profit become unreasonable? In my above example no one was making any profit, but only passing the gil sink to the next buyer by asking what they paid. The effect is multiplied horrendously in the case of medium and large plots.
If the devs and community ended up deciding on a reasonable price and decided to cap the trading price, then everyone would end up having to pay the designated gil loss that comes with each exchange of hands, so what is the point of the higher price? For example, pay the seller the capped 20 mil amount and then pay the game 4 mil to claim a small house, sell forward for the capped 20 mil amount; you still lose 4 mil for owning a house. This is the same as paying only 4 mil and gaining 0 gil from getting rid of it, so why not just forbid any form of house selling? Wanna own a house, pay the set price. No more, no less. It's fair for everyone.