I have three questions pertaining to Ehram.
First: Are we allowed to use unscented halal deodorant while in Ehram? Can we use baking soda/corn starch on our body to stay dry.
Second: Can we use mint flavored toothpaste while in Ehram?
Third: Is it true that while in Ehram we are not permitted to use any clothing like sheets, towels etc that are yellow in color?
Also, Alhamdulillah we are going for Hajj this year. We have been taking out Khums every year for the past several years. However in early stages of his career my husband did not bring Khums out for various reasons one of them being that he was not fully aware about it and now looking back since he was not earning enough and had family responsibilities and loans he was mostly short of cash. That was for 6-8 years. Now how do we figure out how much khums he would have had to take out during those years. We have taken an estimated number but are not sure if it is ok. Will you please help us with this.
InshaAllah I will be praying for your son at Hajj. May Allah, for the sake of His Holy Masumeen, grant him a quick and complete recovery and bless him with a happy and healthy long life. Ameen!

1) Any deodorant is not permissible whilst in ehram unless it’s for medical reasons (one that is needed to avoid excessive harm)
2) Mint toothpaste is allowed but you should avoid smelling it as much as possible
3) Yellow sheets etc in ehram is ok

For khums, try to go back to bank statements on those years and estimate to the best of your ability, asking Allah for help and forgiveness