Yield go down. Valuation go up. All money out.

That's commercial HMO valuation in seven words, and it's broadly true. But it hides the part that actually matters: you don't get to choose your yield. The valuer does. And on a larger HMO, that one number can decide whether you pull all your capital out on refinance or leave a five-figure sum stuck in the property for years.

This guide covers what yield is, how it drives your valuation, and what you can do to influence it.

How larger HMOs are valued

Most residential property is valued on a bricks and mortar basis. The valuer looks at what similar houses nearby have sold for and values yours in line with them.

Larger HMOs are different. Many lenders value them on an investment basis instead, sometimes called a commercial valuation. The property is valued on the income it produces, the same way a buyer would value a shop or an office block. Where the cut-off sits varies by lender, so check how yours will value the property before you commit to it.

The formula is simple:

Value = net income ÷ yield

Net income is the rent you collect, minus the costs of running the property: bills, management, maintenance, insurance, licensing and an allowance for voids. It's before your mortgage payments.

Yield is the annual return a buyer would expect to make on that income, as a percentage of what they pay for it.

Why a lower yield means a higher valuation

This is the bit that trips people up, because a high yield sounds like a good thing.

For an investor buying a property, it often is. A higher yield means more income for every pound they spend. But when you're the one being valued, you want the opposite. A lower yield means a buyer would pay more for every pound of income your HMO earns, so the valuation goes up.

On £90,000 of net income:

• At a 9% yield, the property is worth £1,000,000

• At an 8% yield, it's worth £1,125,000

Same building. Same tenants. Same rent. £125,000 difference in value.

What that means for your refinance

A valuation only matters because of what you can borrow against it. Most HMO refinance lenders will lend up to around 75% of the value, though some lend less.

Say your all-in cost for the project is £800,000. That's the purchase, the refurb, and the fees. Here's what you could pull back out at different yields:

Between 8% and 9%, the difference in what you can borrow is £93,750. One percentage point of yield.

It also shows you something more useful: this deal gets all your money out at any yield up to about 8.4%. Above that, money stays in. That's your break-even yield, and every deal should have one worked out before you buy.

You don't set the yield

The valuer chooses the yield, and they choose it based on evidence. Mainly that's what similar income-producing HMOs in the area have sold or been valued at, adjusted for how risky they think your property is.

So you can't negotiate the yield. But you can control the evidence the valuer sees, and how risky your property looks.

How to de-risk your valuation

Find the comparables yourself

Don't leave it to the valuer to find the evidence. Research commercial HMO sales and valuations in the area, find the ones at the lowest yields you can justify, and put them in front of the valuer with your application. If there are no comparables locally, treat that as a risk in itself.

Prove the income

A valuer will put more weight on income that's already happening than on income you're projecting. Have the rooms let, tenancies signed and the licence in place before the valuation. Some lenders will also want to see a trading history, so check what yours needs before you book the valuation.

Pick the lender for the valuation, not just the rate

Lenders value HMOs differently, including where they draw the line between bricks and mortar and commercial valuations. The cheapest rate isn't always the best refinance if another lender's approach gets you a stronger valuation.

Model at a worse yield than you expect

Work out your break-even yield, then model the deal at a yield above your best guess. If it only works at the best case, it doesn't work.

Run it properly

A compliant, well-managed, fully let HMO looks like a lower-risk investment, and lower risk supports a lower yield. Good management isn't just about the tenants. It shows up in your valuation.

How I use this

Every deal I source is modelled at a conservative yield, with the break-even worked out, before it reaches an investor. If a deal only works on the dream number, it doesn't go out.

For more on the risks to check before an HMO development, read The 10 Risks to Check Before You Commit to an HMO Development. If you're deciding how far to take the spec, read High-End HMO vs Regular HMO.

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