as far as a diy way for humidity I would get a dehumidifer from like the goodwill or another thrift store. That is what I did in regards to mine, all the other options are short term fixes at best and none tend to work fairly well.
For harvest, bud size is not what you should use.... Either get a jewelers lope/pocket microscope and check trichs and harvest at your prefered level of ripeness or just wait til at lease 50% to 75% of hairs have turned red, if not 100% but everyone likes there "buzz"/"high" to be a little different so depending on strain, and your personal pref. harvests can vary.
For harvest, bud size is not what you should use.... Either get a jewelers lope/pocket microscope and check trichs and harvest at your prefered level of ripeness or just wait til at lease 50% to 75% of hairs have turned red, if not 100% but everyone likes there "buzz"/"high" to be a little different so depending on strain, and your personal pref. harvests can vary.