If you can't afford to buy the entire property, why don't you look into purchasing the ground with some others and form a hunt club. I realize it's not the best option in the world, but it's better than not having any ground period. It might actually work to your advantage because you would have more money readily available for plots, stands, etc.

Since your mom owns 1/3 and loves the land, anotheroption is to put it up for auction.Since youown a 1/3 already you would only have to pay for 2/3 of the price. This works to your advantage while bidding on the ground. Essentially, you will either get the ground back for only 2/3 of the sales price or make a fortune and have the ability to purchase a new farm.

Your best option, if you can afford it, is to work out a buy-sell agreement before your relatives decide to sell the property.

Either way, best of luck!