This is what I am sending.
Personal Details Applicant
Signed Application form VAF4A - Personal Details (print-off copy for online application)
Applicants current and valid Passport (with at least 1 blank page)
Applicants Passport sized colour photo9s)(Compliant with UKVI Photo Guidance)
Applicants previous passports (if any)
Tuberculosis (TB) certificate
Evidence of marital status
English Language Test certificate (Compliant with UKVI approved listing)
Personal Details Sponsor
Supporting letter (Not a mandatory requirement but highly recommended as the UKVI caseworkers do read them)
Copy of passport bio page (only include other pages with stamped visas if applicable to the application or supporting evidence). No need for countersigning.
Accommodation
Accommodation details with a supporting letter from the owner/ landlord confirming that you are able to stay there
Tenancy agreement
Council Tax or Utility bill (Recommended but not mandatory)
Evidence of relationship
Marriage Certificate
Divorce decree absolute (if needed)
Photos / Skype records / Facebook messages / Emails etc
Try not to go overboard with kgs of paper/photo's
Completed VAF4A Financial Requirement Appendix 2
Based on standard Category A salaried application
Payslips for the 6 month period up to the date of application (no older than 28 days)
Letter from the employer who issued the payslips
Personal bank statements for the same 6 month period up to the date of application (no older than 28 days)