There is no single all-in reserve figure for every case. Separate qualifying capital from government fees, project charges, professional review, evidence collection and the household’s own living costs.
Avoid spending the same savings twice
Prepare a cash allocation showing which funds support capital, which cover fees and which remain available for family needs. Document the lawful source of relevant administration payments as well. Account for translations or archived records when income spans several jurisdictions.
A project’s projected distribution should not be assumed to replenish savings on the date the family expects to move. Do not allow the same savings to be counted twice, which is the characteristic error where a single accumulated balance is expected to fund everything. Allocate the balance explicitly: the amount to be invested, the amount reserved for professional and government charges, the household's relocation and living costs, and a contingency for the period before any income begins.
Then check what remains against the family's ordinary requirements, including anything that continues at home. Where the investment figure and the household's needs together exceed the balance, that is better known now than discovered mid-process. Add the cost of evidencing the accumulation itself, which for a long history can be significant: archived statements, official copies of tax filings, translations, and accounting support where business and personal accounts were mixed.