I have an 1890 house with a gambrel-like roof. There is a full third floor but a small crawl space for an attic that I am looking to better insulate and ventilate. There are no soffits or attic fans and little insulation and the third floor bakes in the summer and is cold in the winter. There is an hvac unit in the attic space if that makes a difference. Any input would be much appreciated. I am not a diy-er but want to make sure I do the most effective and green job that will not have to be undone later. Do I put in soffits and attic fans and what type of insulation should be used? Cost is an issue, but quality of job is most important. Thanks for any input or recs in advance.