HMO properties have higher yields, but are more complicated to set up. HMO licenses are required depending on the nature of HMO properties.
Traditional rental properties don't have to be located in a particular area. The country's leading letting agents have rented property in virtually every location. They can be rented in any location: rural, urban, or country.
Complex property types are more risky than others. Lenders that don't want to lend to them will not be willing to do so. Those who do will have to meet their individual criteria.
HMOs can be more complicated to manage than traditional buy to rent models. HMOs often have shared facilities, which can lead to tenants falling out. In addition to being a landlord you might also find yourself as a mediator between tenants that don't agree.
Common areas are often left 'as is' because no one wants to clean up another's mess. To maintain their property, landlords might have to clean up or hire cleaners.
A traditional buy to rent model would typically house a household or even a group of people who have made the decision to live together. Disputes are resolved in the home without having to go to the landlord. This is why landlords usually have an HMO type. It could be student buy to let, or an HMO for professionals only.
HMOs often come furnished. This is another cost to be aware of. Traditional buy to rent properties are usually unfurnished.