I am interested in building a high quality sun room, to replace an existing concrete patio area. I am finding that the firms that specialize in these rooms charge quite a lot for them, typically $30K to $60K for rooms that are often under 300 squore feet. That seems high for what you get to me, given what looks like low costs for the materials. One contractor told me that the material costs for the sunroom are typically only about 25% of the project cost, and most of the cost is in the labor.

Can someone familiar with these products let me know:

1) Who are the highest quality companies making prefabricated rooms? The one that quoted me was "Four Seasons".

2) Are there vendor who will sell you just the materials and let you use your own contractors for assembly?

3) Are these products really tricky to install and is there a reason to avoid do-it-yourself projects?

4) Are there any tricks to help get costs down?