The mistake that sinks more portfolios than a bad tenant: running the numbers on a spreadsheet that still pretends Section 24 doesn't exist.

I started buying HMOs in Leeds in 2016, back when mortgage interest was still fully deductible against rental income and a "20% yield" deal was exactly that: a 20% yield deal. Section 24 of the Finance Act 2015 changed that. From April 2017 it began phasing out full mortgage interest relief for individual landlords, replacing it in stages with a flat 20% tax credit, fully in effect by the 2020/21 tax year. If you're a higher-rate taxpayer, that's the difference between paying tax on your actual profit and paying tax on your turnover before finance costs. My first HMO, a six-bed student let, looked like a 22% gross yield deal on the day I bought it. By the time Section 24 had fully phased in and the base rate had climbed through 2022 and 2023, the same property was barely covering its mortgage once tax was accounted for properly, and I came within a fortnight of selling at the bottom of the market because a lender's stress test on refinance said I couldn't afford my own portfolio. What saved it was restructuring into a limited company for new purchases and working through, property by property, which of my personally-held HMOs were worth incorporating despite the tax that transfer usually triggers. Four years on, the portfolio spans fourteen units across Leeds and Bradford, all licensed, all stress-tested against a rate environment that isn't going back to 2016.

The detail matters more in property than in almost any other UK business, and it's rarely explained properly before someone's already exchanged. An Article 4 direction removes the permitted development right that normally lets a family home convert to a small HMO without planning permission, meaning a deal that pencils out perfectly in a non-Article 4 postcode can be un-mortgageable and unlettable two streets over. Leeds, Manchester, and Birmingham all run selective and additional licensing schemes in specific wards on top of the mandatory HMO licensing that kicks in at five or more occupants from two or more households, and operating unlicensed doesn't just risk a fine, it exposes you to a Rent Repayment Order that can claw back up to twelve months of rent. Portfolio landlords with four or more mortgaged properties are underwritten differently since the PRA tightened standards in 2017, meaning a lender now stress-tests your whole portfolio's affordability, not just the property in front of them, and margins have narrowed further as EPC minimums for let properties, currently band E with band C proposed, push older stock toward retrofit costs that weren't in anyone's model a decade ago. Get any one of these wrong and the deal that looked good on a spreadsheet becomes a liability you can't refinance your way out of.

What we cover inside:

Numbers before narrative. Every deal discussed in this group gets underwritten on realistic assumptions: post-tax cash flow after Section 24 or corporation tax depending on structure, void periods based on actual HMO turnover rather than best-case occupancy, a proper maintenance reserve, and specialist HMO landlord insurance rather than a standard buy-to-let policy that won't pay out on a multi-let claim.

Compliance as a moat. Article 4 status, licensing requirements, and EPC rating get checked against a property before an offer goes in, not discovered during a mortgage valuation. Members use a live checklist built from real council licensing registers, because the boundaries of these zones change and a postcode that was clear last year isn't necessarily clear now.

Structure and tax. Buying personally versus through a limited company isn't a one-size answer. We work through the actual decision, your income tax band, whether you're building to hold or to trade, and whether the SDLT and CGT cost of incorporating an existing personally-held property is worth it against years of Section 24 drag.

Deal sourcing and refinancing. Most of what gets discussed didn't come from Rightmove. Members share how they've built relationships with agents for off-market stock, and how to structure remortgages and further advances so growth past the first two or three properties doesn't depend on finding a fresh deposit every time.

Every fortnight there's a live deal clinic on Tuesdays where members bring a real HMO or buy-to-let they're considering and we pull it apart together on screen, post-tax cash flow, voids, refinance risk, licensing status, the lot, before anyone puts down a deposit. Alternate Sundays cover market updates and licensing changes across the group's core cities, so members hear about a new selective licensing designation the week it's announced rather than after they've already bought into the ward. Inside the group you'll also find the stress-test spreadsheet template used in every clinic, a regularly updated Article 4 and selective licensing reference by city, and warm introductions to brokers who actually understand portfolio and HMO lending rather than generic residential mortgages. New members typically start by bringing their next prospective purchase to a clinic rather than a hypothetical, because the feedback only bites if the numbers are real.

This is built for people buying their first HMO or buy-to-let through to landlords running a portfolio of twenty-plus doors who want their assumptions checked by people with more properties than opinions. It isn't built for anyone looking for a guaranteed return, a no-money-down shortcut, or a reason to skip the licensing check because the numbers "feel" right. If you want to be told what you want to hear about a deal, this group will disappoint you; if you want someone to find the flaw in your spreadsheet before your lender does, it won't.

✅ Live deal stress-tests using real Section 24 and interest-rate assumptions
✅ Article 4 and selective licensing checklists for Manchester, Leeds, and Birmingham
✅ Direct access to brokers who specialise in portfolio and HMO lending
✅ A structured framework for the personal-ownership-versus-SPV decision

Members who stick with the fortnightly rhythm typically avoid at least one costly mistake in their first year, a licensing breach caught before exchange, a refinance planned early enough that a rate rise doesn't force a fire sale, or a deal walked away from before it ate a deposit. If you want a portfolio that still works after tax, not just before it, join the group.