When it comes to sunrooms and patio enclosures, there are a wide variety of styles and structures that can vary in cost from $20,000 to upwards of $45,000. Before you buy one, you need to consider several factors.
Type of Use: If you simply want a breezy area to sit in the warm months during Spring, Summer and Fall, then a lighter weight, manufactured patio room might be best for you. You will feel connected more to your yard and garden than your house in this type of sunroom. These type of rooms are usually available in 3 or 4 basic colors (white, tan, beige, for example). They typically aren’t heated or cooled and are not used in winter.
If you want to add on to your home’s livable year-round space, with an interior and exterior that seamlessly match your current home, then an all season room addition would be best for you. This type of room can be sided to match your home with siding and or stone; with heating and cooling similar to the rest of your house.
Budget: A three season sunroom is an economical choice. It’s a good option for getting good, livable space for two thirds (or more) of the year. For a year round addition to your home, you should budget in the $40,000 range.
Resale Value: Be aware that value priced, manufactured rooms may not increase your home’s value and could actually be a detractor. Over time, these rooms do not weather as well and according to Marianne Cusato of the University of Notre Dame, are often the first thing a new owner will remove from the home. So if you plan to sell your home soon and want to get a top price, this is not the best choice. All season rooms that match the exterior of the rest of the house create the most resale value.
 Qualified Remodeler magazine, June 2016