I don't have any gutters on my house now but I am planning on it soon. There is plastic under the house already but some places need replaced. Will do that soon also (after the duct work is done). You said a dehumidifier for the short term what do you mean by "short"? Is there is certain dehumidifier for the situation or just use any one? I have 1053 sq ft of crawl space and 8 vents on the outside.