Two tools answer different questions
Manual design answers “Where will the products go?” Rendering answers “How could this design look on this property?” A contractor needs both answers. Placement depends on access, scope, product choice and what the customer will pay for. An attractive generated image cannot make those decisions on your behalf.
Prompt-only tools can help explore a general mood. They can also introduce details outside the scope. A controlled workflow starts with deliberate placement so the rendering system has a stronger description of your intent. That improves the usefulness of the input without making the output infallible.
Keep installation decisions in the manual design
Mark the runs and regions you plan to light. Select colors, patterns and product appearance deliberately. If two alternatives differ only in the roofline color, preserve the same placement so the customer can compare the decision that matters.
RendrPro provides manual Studio access without consuming credits. Rendering is a separate step, so you can refine a layout before spending a Rendr Credit. This is useful when the customer is still deciding scope: work on placement first, then render the version that merits presentation.
Use realism when it answers a sales question
A manual layout may be enough to confirm which eaves and trees are included. A photorealistic visualization can help when the customer is comparing the overall appearance of a simple roofline with a fuller display. Choose the output based on the decision, rather than generating another image after every small edit.
Keep the original photo available during review. Compare the proposed illumination, structure and product placement. Do not accept an unintended addition just because it looks appealing; either remove it or explicitly revise the scope and price.
Evaluate tools on a real, repeatable property
Use the same approved source photo and base design to compare software. Note whether you can reopen a saved layout, create an alternative, correct a result and export it with the appropriate branding. Test on the device you use at appointments.
Price is only one part of the decision. Also check how credits work, whether free access continues, and whether project organization fits your business. Avoid judging accuracy from a single vendor showcase. Your own representative property is a better test of workflow fit.