How a quote is built, line by line
Most quotes combine a percentage of rent with fixed charges for defined events, and the percentage model dominates because it scales with the rent.
The headline number is usually a percentage: 8–15% of monthly rent for full management, or 5–10% of the first month's rent plus VAT for let-only. A flat per-property figure sometimes appears instead, but the percentage model dominates.
What the percentage must not do, in England, is quietly reappear on the tenant's side. Since 1 June 2019 the Tenant Fees Act has banned most tenant-facing fees; the holding deposit is capped at one week's rent and the tenancy deposit at five or six weeks, depending on the annual rent.
Because the ban removed a revenue line, the landlord's management fee is now where the full cost of compliance work tends to sit — one more reason two quotes can differ without either being wrong.