How do I enter home expenses for two businesses that operate from the same home office space at different points in the year? Should I claim all expenses in one business?

You can claim home office expenses for both- and just claim for the months you used the space for each business since you used the same space for both at different times.

if one business was 50% personal use and the other business was 100% at same home do I just put same amount for costs of insurance and home expense on both including property tax? or different amount (electricity etc). the rooms I used in the house are different.