Funding should match risk. A platform with custom software, low collateral, and uncertain demand is not financed like a local retail shop. Early costs are mostly people, product, marketing, legal, and working capital. Lenders will want repayment capacity; investors will want evidence of marketplace liquidity and scalable unit economics.
The SBA says 7(a) loans can be used for short- and long-term working capital, equipment, supplies, refinancing, and other business purposes, with a maximum loan amount of $5 million, according to its 7(a) loan program page. For a marketplace, SBA financing may fit an operating company with owner equity, clear credit, and repayment capacity, but venture capital or angel funding may fit better if the plan assumes fast growth and heavy losses before break-even.
Debt is most dangerous when used to fund unproven paid acquisition. Equity is most expensive when raised before the founder has evidence. A balanced plan funds the next proof point: seller supply, buyer conversion, repeat purchase, or contribution margin.