I was just telling a buddy about one of the many background stories on New Vegas, the subject of Vault 21 deciding everything on gambling. We know House won the vault and forced them to leave, what I did not remember and don't think it ever says is what he risked? Do you think it was money? I don't think it was as simple as that, it would have to be something worth the risk of leaving their home? Just wanted to see what you all thought he may have wagered.

I think it was something they actually needed, like food, medicine or water.

Most likely had House lost the bet he would've sent Securitrons and troops from the vegas families to "evict" them. House has only ever played by his rules.

Except when he refuses to send Securitrons into the casinos as it's part of his contract with the Three Families. Despite the fact that he believes the Omertas are plotting against him.

I would say one of two robots for mundane tasks.

Their independence from Mr. House, no doubt. Or perhaps a steep payment to buy their Vault.

"A kind word and a gun..."
Or in this case,
"An offer to play fair and square for the property, against a mountain of assets, under implied threat of death by securitron".