It is a legitimate option that suits a minority of people, and it is usually pitched without the parts that make it hard.
You keep an appreciating asset, you generate income, and you do not have to say a final goodbye to a house you raised a family in. For a household that can genuinely afford it and wants exposure to property, it can work.
If the equity in your current home was funding the purchase, keeping it means financing the new property another way. Qualifying to carry two properties is a different conversation with a lender than qualifying for one, even with expected rent counted — and lenders discount projected rental income rather than taking it at face value.
Converting your principal residence to a rental has real tax consequences, including how the principal residence exemption applies for the period it was rented. This genuinely needs an accountant before you decide, not after. Getting it wrong is expensive and difficult to unwind.
This is the one people underweight. The reason many people downsize is to stop maintaining a house. Renting it out means still maintaining it, plus tenants, plus vacancy, plus the furnace failing at 11pm in January — only now it is not your furnace to live with, it is your obligation to fix immediately.
A property manager solves much of that for a percentage of rent, which changes the arithmetic.
The features that made it a fine family home — size, a big yard, an older kitchen, dated systems — may not produce a strong yield relative to its value. Run the actual numbers on rent against the property's current worth, not against what you paid for it decades ago.
If three of those four are yes, it is worth serious consideration. If two or fewer are, selling is usually the cleaner path — and cleaner has real value at this stage of life.