Buy to Let Costs Checklist

Most buy-to-let cost estimates focus on the mortgage payment and the letting agent's fee, then miss half the actual bill. Between acquisition costs you only pay once, annual running costs that recur every year, and capital expenditure that arrives unpredictably every few years, a realistic buy-to-let budget has far more moving parts than rent minus mortgage.

This checklist works through all three categories, plus how to size a maintenance reserve so the capex line does not derail your cashflow when it lands.

Acquisition costs

These are one-off costs that apply when you buy, whether it is your first buy-to-let or your fifteenth:

• Deposit. Typically the largest single cost, and the amount depends on the lender's required loan-to-value for buy-to-let, which is usually higher than for a residential mortgage.
• Mortgage arrangement and broker fees. Buy-to-let mortgages commonly charge an arrangement fee, sometimes added to the loan rather than paid upfront, plus a broker fee if you use one.
• Stamp Duty Land Tax, including the additional-property surcharge. Buy-to-let purchases usually attract a surcharge on top of standard rates. Rates and thresholds change, so check our buy-to-let stamp duty calculator for a current estimate rather than relying on a figure from an older article.
• Survey and valuation. A lender's valuation is usually required as part of the mortgage; a more thorough survey (a homebuyer's report or full building survey) is optional but worth it for an older property or one you have not inspected closely.
• Legal fees, covering conveyancing on the purchase and the mortgage itself.
• Initial refurbishment, if the property needs work before it can be let, including anything required to meet minimum safety and energy efficiency standards.
• Initial safety certificates, such as the first gas safety check, EICR and EPC if the property does not already have valid ones. Our landlord certificates checklist covers what is mandatory before you can legally let a property.

Annual costs

These recur every year, whether or not the property is occupied for the whole of it:

• Mortgage interest, which moves with your rate and, for anyone coming off a fixed deal, can change significantly at renewal.
• Letting agent or management fees, if you use one, typically charged as a percentage of rent for a let-only or fully managed service.
• Landlord insurance, covering buildings and, where relevant, contents and loss of rent. Our landlord insurance guide covers what a typical policy includes and where cover gaps commonly appear.
• Compliance costs, including the annual gas safety check, an EICR every five years (so budget roughly a fifth of the cost each year), and any HMO or selective licensing fees that apply to your property.
• Ground rent and service charge, for leasehold flats, which can vary enormously by building and sometimes rise faster than rent.
• Void periods, meaning weeks the property sits empty between tenancies with no rent coming in but costs (mortgage, insurance, council tax) still due.
• Accountant or bookkeeping fees, for preparing your Self Assessment return or, if you hold property through a limited company, statutory accounts.
• Repairs and maintenance, the day-to-day fixes that come up during a tenancy, separate from the larger capital items covered below.

Capex

Capital expenditure is the category most landlords underestimate, because it does not happen every year, which makes it easy to leave out of a monthly budget until it lands as a large, unplanned bill:

• Boiler replacement, typically needed every 10 to 15 years depending on usage and maintenance.
• Roof repairs or replacement, which can range from a minor patch to a full re-roof depending on age and condition.
• Kitchen and bathroom refurbishment, both to keep a property competitive in the local rental market and, eventually, because fixtures wear out.
• Rewiring or electrical upgrades, sometimes triggered by an EICR identifying remedial work that goes beyond routine maintenance.
• Energy efficiency improvements, which may become unavoidable rather than optional as Minimum Energy Efficiency Standards tighten on the private rented sector over the coming years.
• Windows, doors and exterior work, which affect both energy efficiency and general condition.

None of these capex items are unusual. They are the ordinary lifecycle of owning a property, and the only real question is whether you have planned for them or whether they arrive as a surprise.

A worked example shows how this plays out over a holding period. A landlord budgets month to month for mortgage, insurance and letting agent fees, and things look comfortable for the first four years. In year five, the boiler fails and needs full replacement, the EICR flags remedial electrical work, and a void period between tenants adds a further gap in rental income, all within the same six months. None of these were unusual or unlucky individually, they were simply capex and voids that had not been budgeted for because the landlord's monthly numbers only ever covered recurring annual costs. A reserve built up over the previous four years would have absorbed all three without needing to dip into personal savings or delay the work.

Build a reserve

The most reliable way to avoid capex catching you out is treating it as a certain, if irregular, cost rather than an unexpected one. Many landlords set aside a portion of monthly rent into a separate account specifically for maintenance and capex, building a reserve during the years nothing major happens so it is there when something does.

How much to set aside depends on the property's age, condition and systems. An older property with an ageing boiler and single-glazed windows needs a larger reserve than a newer build still under warranty on most major systems. Reviewing what capex is realistically due in the next five years, roughly costing it, and dividing by the months until then gives a far more grounded monthly figure than an arbitrary percentage of rent.

Tracking this reserve alongside your day-to-day income and costs matters more as your portfolio grows, since a single property's capex needs are easy to hold in your head, but ten properties with staggered boiler ages, roof conditions and EICR dates are not. Our rental yield calculator guide shows how to build a realistic annual cost estimate, including a maintenance allowance, into your yield figures so a property's true return already reflects the capex it will eventually need.

A reserve is only useful if it is actually kept separate from working cash. Money sitting in the same account as rent income and mortgage payments has a habit of getting spent on whatever feels urgent that month, whereas a dedicated savings account, funded by a fixed transfer each time rent comes in, is far more likely to still be there when the boiler finally fails.

How Property HQ helps

Property HQ's finance view tracks income and costs per property against your connected bank feed, so you can see a true net position, including a reserve building for future capex, rather than a headline profit figure that ignores the boiler, roof or rewiring bill that is coming eventually.

Disclaimer

For a live total, use our free buy to let costs calculator.

This guide is general information for UK landlords, not tax or financial advice. Costs vary by property, area and lender, and tax and statutory rates change over time - check current figures on GOV.UK or with a qualified adviser before budgeting for a purchase.