It's like asking a bodyguard to take a bullet for you, just to prove that they'd really take a bullet for you.
It would be less off-putting if they said "You put in the first $150k and build it for six months and if we invest then we guarantee that you can take your $150k off the table (if you want too)."
It would be less off-putting if they said "You put in the first $150k and build it for six months and if we invest then we guarantee that you can take your $150k off the table (if you want too)."