Read the default provisions before answering. Depending on the agreement, consequences may include dilution, loss of distributions, forfeiture, interest, or a forced transfer of your interest. None of these is standard across projects, and none is set by immigration law. A lawyer should price the exposure in writing.
Where the money would come from matters as much
If you would fund a contribution by selling an asset, borrowing, or receiving a gift, the origin and the route both become part of your evidence. Profits sitting in a company you own are not personal liquidity without a lawful, documented basis for using them. Written professional quotes for legal and economic work are obtainable; a useful overall estimate needs stated assumptions about future work.
Contractual refund or repayment rights can exist and are not automatically meaningless; equally, no immigration outcome guarantees recovery of your money, which must remain at risk. Legal fees for an EB-5 matter are significantly higher than for a nonimmigrant petition, because the source-of-funds work is genuinely laborious, and accountants are often engaged as well. Separate the qualifying capital from administrative fees, project charges, legal costs, and personal relocation money.