Rebuild a personal or team monthly budget from scratch when the old spreadsheet stopped matching reality

You are helping rebuild a monthly budget from zero because the existing one has drifted so far from actual spending that patching it is no longer worth it. This is a structuring exercise, not financial advice — you are organizing the requester's own numbers into a clearer shape, not telling them what they should be spending or saving.

INCOME SOURCES
Salary $5,400/month after tax, freelance design work averaging $600/month over the last 3 months.

KNOWN RECURRING EXPENSES
Rent $1,800, car payment $310, phone $65, gym $40, streaming subscriptions $38 total.

VARIABLE SPENDING CATEGORIES
Groceries ($400-550), dining out ($150-300), gas ($120-180).

BUDGETING METHOD REQUESTED
Zero-based — every dollar assigned somewhere, nothing left unaccounted for.

TIMEFRAME
Calendar month, starting the 1st, aligned to when rent is due.

RULES
Build the budget so every dollar of listed income is assigned to a category, a savings goal, or an explicit "unassigned" line — never let a difference between income and listed expenses vanish silently. Where a recurring expense could plausibly vary month to month (utilities, variable-rate anything), flag it as an estimate rather than presenting it with the same certainty as a fixed rent or subscription figure. If the requested budgeting method (zero-based, 50/30/20, envelope, etc.) doesn't fit cleanly with the categories given — for instance a 50/30/20 split when no expense has been tagged as a "want" versus a "need" — say so explicitly and propose the smallest change needed to make the categories usable rather than forcing a fit. Do not invent an expense category the requester didn't mention just because it's common (e.g. don't add "entertainment" if it wasn't listed); ask instead. Close with a short list of every number you had to assume or estimate rather than were given directly, so the requester knows exactly what to verify against their bank statement before using this.

OUTPUT FORMAT
1. A table: category | monthly amount | fixed or estimated | % of total income.
2. The unassigned/surplus or shortfall line, called out plainly.
3. Three to five specific follow-up questions that would tighten the accuracy of this budget.
4. The assumptions list described above.