I'm afraid skylights might leak or increase the cost. 

Kyle PotswaldCitizens first position HELOC CMG a financial 70% LTVEast West Bank, up to 60% LTV with "no docs” Figure 80% on a rental, not in LLC First Florida Credit Union https://firstflorida.cumortgagecenter.com First CommonwealthGreat Lakes Credit Union HSBC 70%, for premier clients only Huntington 75% LTV Hurst Lending and Insurance Investment property HELOC in Texas.

DSCR would be an option, however, if you can qualify for a full a documentation loan your rate and terms (like your upfront closing costs and pre-payment fee that come with most DSCR options) are better with a full doc loan.

There were no visible signs of  leak above the ground.

It started with the "heartbreaking" single family houses, full of run down yards, overgrown trees, ceramic sewer pipes, leaking galvanized water pipes and Cochroaches throughout.

I don't work for RETA, I am a semi-retired doc in Port Moody, BC, Canada. 

Scope of Work:Initial Assessment: Our team conducts a thorough assessment of the property to evaluate its current condition, identify structural issues, and determine the scope of renovation required.Design Concept: Collaborating with architects and designers, we develop a design concept that blends contemporary elements with the historic character of the row house, maximizing space utilization and optimizing layout efficiency.Structural Repairs: Structural repairs and reinforcements are undertaken to ensure the integrity and stability of the building, addressing any foundation issues, roof leaks, or structural deficiencies.Interior Renovation: The interior of the row house is completely renovated, including the removal of non-load-bearing walls to create open-concept living spaces, installation of new flooring, upgrading electrical and plumbing systems, and installing energy-efficient fixtures and appliances.Kitchen and Bath Remodeling: The kitchen and bathrooms are transformed with modern finishes, custom cabinetry, quartz countertops, and high-end appliances, creating functional and stylish spaces for daily living and entertaining.Historic Preservation: Special care is taken to preserve and restore original architectural features such as exposed brick walls, decorative moldings, and hardwood floors, enhancing the property's historic charm and character.Exterior Enhancements: The exterior of the row house receives a facelift with fresh paint, repaired masonry, restored windows, and landscaping improvements, enhancing curb appeal and contributing to the overall aesthetic appeal of the neighborhood.Quality Assurance: Throughout the renovation process, our team adheres to strict quality control measures and standards, ensuring that workmanship meets or exceeds industry best practices and building codes.Finishing Touches: The finishing touches, including interior decor, lighting fixtures, and hardware, are carefully selected to complement the design aesthetic and create a cohesive and inviting atmosphere.Timeline and Budget:The single-family flip project in the Philadelphia row house is estimated to be completed within [timeline], with a budget of [budget].

The only way to avoid that is if you are using a Bank Statement loan or a DSCR program on an investment property since those are "No Doc" but still require bank statements for assets.The days of walking into a bank and doing business on a handshake are gone.  

Finding maintenance issues prior to them becoming a larger problem (water leaks, pipes, roof etc.).

I am also willing to bet you dinner somewhere that the loan docs on the underlying mortgage have somekind of prohibition on doing exactly what is being done.