Landlords can currently deny tenants who want pets, and some have charged “pet rent”.

Well, it does bring extra issues for the landlord, so I suppose that having a pet fee is reasonable, but it sounds like there's a fair argument that the demand is undersupplied today.

This is for the US, but I wouldn't be surprised if numbers hold.

https://www.tenantcloud.com/blog/pets-in-rental-properties-a-guide-for-landlords-and-tenants

After surveying 1,000 tenants, it was found that approximately 90% of renters have pets. On the other hand, around 69% of landlords do not allow pets in their rental properties due to concerns about potential pet-related issues such as odor, property damage, lack of training, noise complaints, and the property's suitability for pets. In a competitive rental market, landlords may choose not to risk losing potential tenants who don't have pets. One solution to this issue could be for renters with pets to pay an increased deposit to cover possible damages. However, around 88% of pet owners have never had any complaints or caused any damage to rental properties.

Let's take a closer look at some of the pros and cons of renting to pet owners to better understand the implications of such a decision.

Pros:

1. Increased Demand: Allowing pets in your rental property can open up your pool of potential tenants, as many pet owners struggle to find pet-friendly housing.

2. Higher Rent: Pet owners are often willing to pay a higher rent or a pet deposit, which can increase your rental income.

3. Longer Tenancy: Pet owners tend to be more settled and stay in one place for longer periods, which can reduce tenant turnover and vacancy rates.

4. Responsible Tenants: Pet owners are often trustworthy and caring and most likely will treat your property with respect and care.

5. Emotional Support: For some tenants, having a pet can be a source of emotional support and can aid mental health issues.

Cons:

1. Property Damage: Pets can cause significant damage to a rental property, including scratches, stains, and odors, which can be costly to repair.

2. Noise Complaints: Barking dogs and meowing cats can be a source of disturbance to other tenants and can lead to noise complaints.

3. Liability Issues: If a tenant's pet injures someone or causes damage to someone else's property, you as the landlord may be held liable.

4. Cleaning Costs: Even well-behaved pets can shed hair and dander, which can require additional cleaning and maintenance between tenants.

5. Lease Violations: Some tenants may try to sneak in a pet without your permission, which can lead to lease violations and legal issues.