Investors & landlords

On converting from income property to personal use and NOT primary residence, on scad E

 just complete what percent personal use and for the entire year it would be 100 % or what ever date in the year to take effect. If 365 days or 100 % personal use, there are still SOME tax deductions that qualify ? Such as Taxes I presume ?

Can I do the same conversion for a total of 2 single family renal  houses ?

Dan