If you already have an investment property perhaps you could renovate to add an extra bedroom and get the rents up.

Especially if you're renting, I'd say 100% get into a house-hack.  

It needed minor cosmetic updates, I was able to do most of the work myself and it has been rented out since last summer.

A triplex fully rented out that currently generates an income of 3K.

5) Collect rent?

She pays the rent on time but is generally difficult to deal with. 

I rent to people who set up mid and short term rentals.

It has been rented out the past (4) years and has good equity.

Lenders will use the market rents or lease rents to qualify you instead of your personal debt to income ratio.

Let's explore some effective approaches for managing investment properties:With a Property Manager:Screening and Selecting Tenants: Entrust your property manager to handle tenant screening, background checks, and selection, ensuring reliable renters for your investment.Rent Collection: Property managers can ensure timely rent collection and handle any late payments or lease violations professionally.Maintenance and Repairs: Delegate routine maintenance tasks and repairs to your property manager, who can coordinate with contractors and vendors to keep your property in top condition.Tenant Relations: Property managers serve as the primary point of contact for tenants, addressing their concerns and ensuring a positive rental experience.Lease Enforcement and Evictions: Trust your property manager to enforce lease terms and handle the eviction process if necessary, following legal procedures.Financial Management: Property managers can handle financial tasks such as budgeting, accounting, and financial reporting, providing you with regular updates on property performance.Without a Property Manager:Self-Management: Take on the responsibility of managing the property yourself, handling tasks such as advertising vacancies, screening tenants, and collecting rent.Outsourcing Specific Tasks: While not hiring a full-time property manager, consider outsourcing tasks like maintenance and repairs to trusted contractors or service providers.Utilizing Technology: Leverage property management software and online platforms to streamline processes such as rent collection, lease management, and maintenance requests.Establishing Clear Policies: Set clear policies and procedures for tenants regarding rent payments, maintenance requests, and lease terms to minimize conflicts and misunderstandings.Regular Inspections: Conduct regular inspections of the property to identify maintenance issues or lease violations early on and address them promptly.Building Relationships: Maintain open communication and positive relationships with tenants to foster a sense of community and encourage better care of the property.Whether you choose to hire a property manager or manage the property yourself, effective communication, attention to detail, and a proactive approach to property management are key to maximizing returns and maintaining the value of your investment.