This enterprise's actual cost determines the proportional analysis; a mobile model is not necessarily cheaper than a fixed-location business. E-2 has no universal minimum. Document investment and economic capacity without assuming low overhead alone establishes substantiality or non-marginality.
Budget the whole start-up, not just the van
Count vehicles and fitting-out, tools, software, licensing and bonding, insurance premiums, marketing, and the operating funds needed until receipts cover costs. A working-capital reserve is a planning example, not a legal requirement, and its size depends on the trade. Keep government fees checked against current published figures, and record immigration-preparation legal fees separately from business expenditure so their treatment can be reviewed on the facts.
Substantiality is proportional, so the denominator matters as much as the amount invested. Establish what this specific enterprise costs to start and to run, using quotations, invoices and the actual price of the licensing and insurance required, and the proportion becomes a calculation rather than an assertion. What goes wrong is comparing against a general impression of what businesses cost.
A low total is not automatically fatal and a high total is not automatically sufficient; both are read against the enterprise being built. Keep the record of what has already been irrevocably committed separate from what is merely planned, because the two answer different questions and merging them weakens the stronger half. Confirm official charges from current published figures at the time of filing.