Taxes Asset Declaration

Hello im new to the forum and only been in Mazarron since May 2019,my partner and i have got our residency but now have to sort out the tax situ here,i understand there is a form 720 Asset Declaration form which needs to be completed, my concerns are,

1.the amount of cash that is banked in the U.K what is the limit before tax here in Spain,

2.I have a property in the uk which is rented out will i be taxed on that.

3,what is the % tax here.

Thank you in advance for any help and information.