Thanks for your question.
If you are in a relationship with your partner and are going to be living together as a couple then a cohabitation agreement is more appropriate to your situation.
A cohabitation agreement is a deed signed by both parties which states whether or not each party is to have/accrue an interest in the house and if your partner is to contribute money to the household expenses then it will specify this as well. It will also deal with other things such as property bought during the course of the cohabitation, debts, budgeting and payment of outgoings.
In order for it maximum likelihood of standing up in court you should both take independent legal advice on the document and be completely honest with each other about what you both earn. You daughter will also need to be a party to the cohabitation agreement.
If he is to occupy the property then you will need to speak to your mortgage company about what they require so that you do not breach a term of your mortgage with them., They will likely require that your partner executes a deed of postponement stating that he has not and will not acquire any interest in the property and will agree to vacate it in the event that it is sold. He will have to take this to a solicitor to execute it and it will cost in the region of £70.00 +VAT.
A lodger arrangement is more appropriate where you have an independent private person with whom you do not have an intimate relationship.
A cohabitation agreement would likely cost in the region of £400.00 from a local solicitor and although you may be reluctant to spend that amount of money it may be worthwhile since you could get him to sign a self-drafted document but if that is then found to be unenforceable in the future for whatever reason then you could be faced with legal fees much higher than the cost of the agreement in sorting it out.
I know it's probably a somewhat clinical approach to what will no doubt be a happy time for you both, but hopefully he will see that it is advisable in the long term.
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