First things first, child maintenance and seeing your child are completely separate things - in law anyway.
Whilst coming to an informal agreement is always best for the children, I understand that is not always possible.
A mediator can sometimes help and they can help you draw up agreements between you. These wouldn't normally be legally binding however. You can explore this here: https://www.familymediationcouncil.org.uk/find-local-mediator.
If you feel that you've reached the stage where court is necessary then you could consider applying to the court for an order called a Child Arrangements Order (CAO).
Specifically within a CAO it often dictates who the child is to live with. You can apply for the child to live with you or for a joint live with order which is what people sometimes refer to as "joint custody".
You don’t have to apply for a live with order, you can just apply to spend time with the child which is what people sometimes refer to as “contact”.
You can instruct a solicitor to apply for this for you or you can apply yourself.
You can find a solicitor who specialises in family law here: https://solicitors.lawsociety.org.uk
If you wanted to apply yourself then you can find the form here: https://www.gov.uk/government/publications/form-c100-application-under-the-children-act-1989-for-a-child-arrangements-prohibited-steps-specific-issue-section-8-order-or-to-vary-or-discharge
You will have to pay an issue fee (£215) to the court but if you are on a limited income then sometimes you can apply for a remission: https://www.gov.uk/get-help-with-court-fees.
Before you issue an application, you are expected to try to negotiate and attend a mediation assessment session (MIAM). You can find information about this here: https://www.familymediationcouncil.org.uk/family-mediation/assessment-meeting-miam/. There are exceptions in certain circumstances e.g. urgency.
If you do issue an application usually what happens is when the case is first listed, Cafcass inform the court about any safeguarding issues. Often the court needs more information and order a s.7 report. If appropriate this includes finding out the “wishes and feelings” of the child. You can find out more about s.7 reports here: https://www.cafcass.gov.uk/grown-ups/parents-and-carers/divorce-and-separation/section-7-report/
The case only progresses to a contested hearing with a judicial decision if an agreement cannot be reached between yourselves.
In general the court will always look to encourage a relationship between the child and both parents if it is safe. The overriding factor in any decision is always the welfare of the child.
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