3 months is not at all acceptable. I completely agree with the others that you shouldn’t have allowed this much time. Actually most landlord make the mistake of not making a contract when the renter is taking hour house in rent. This allows them to take the chance. There are hundreds of incidences where the renter has fled away with a due rent of even 12 months! Yeah this is absolutely true. If you keep your goalpost open, you are bound to concede goals! So it is the responsibility of all landlords to make a legal agreement while giving the house in rent.
Also the landlords should ask the renter for their personal documents such as identity card, driving license etc. This is to ensure that you are giving your house rent to a genuine person, not any fake identity. Also you can verify the identification by testing them in the local police station. If you are 100% confirm that the person is genuine then you are free of many risks. Even if the renter invades away anytime, you can take steps to catch him as you have all the documents in your collection. Without doing all this, giving rent is not free from risk.