There could be a time that you will have to make the decision to let your elderly parents or even in-laws come and live with you. There could be a variety of reasons for this decision but what matters is that you are able to make it a good arrangement for everyone involved and that it doesn't become a burden on anyone. This can be very stressful for all parties so it's a good idea to do your best to try and lower those stress levels.
The first thing that you need to do is to make sure that you discuss the whole situation well in advance of them moving into your home. You need to realize that your parents are use to being able to live independently in their own place and this could be as hard for them to adjust to as yourself.
You should talk about all the different issues that you think might come up before they try to get settled in and try to create an atmosphere of mutual trust and respect and try to come to any compromises ahead of time that is going to work for everyone who lives in the home together.
Even though they may be your parents, it's still your home and with as much tact as you can manage to muster up, you do need to establish what your particular house rules are. Each person needs to agree to having their own responsibilities as well as their own limitations within your home. It's important to note to everyone in the family that everyone does have their own identity and that bringing in elderly parents and adding this to the formula that already exists can disrupt the harmony of the family for a short while. So be prepared for that and make sure that your family is as well.
If you still have children living at home, you need to consider them as well. Even though the kids may love their grandparents dearly it still can be kind of a hard adjustment for your kids especially if they are teens. So it's important that some boundaries are set and make sure they are boundaries that everyone can agree to live with. You children also need to be aware that they need to be considerate to their grandparents and the grandparents also need to understand they need to step back while you dish out the discipline when it's needed.
Everyone needs and deserves their own privacy so make sure that is something that everyone is assured of. Make sure that your parents room has everything they might need so that they will feel as self sufficient as they can. This might mean putting in a small refrigerator and a microwave for times when maybe they just want to be alone and eat in their room with one another. Anything to make them feel like they have their own space.
Your parents are use to having their own furniture and things for years and years, but it's obvious you are not going to be able to let them bring all of their own things with them. However, you might be able to rearrange things where they can add some of their things, especially in their own room. Other things will need to be sold, stored away or given to other relatives.
You should discuss a budget to see if your parents are going to pitch in on the expenses or are they just going to cover their own and you will need to cover everything else. Whatever you do, don't assume anything when it comes to the finances. You definitely need to discuss this before they move in.
If your parents are physically able to help around the house and they show interest in doing so, then let them. This will help them like they are worth something and that they are still useful. This can be a very difficult and emotional time for them and the last thing you want is for them to feel worthless.
Final Note: Be encouraging and try to convince them to stay independent and active this will be a big help for their emotional health. Patience, very key here. You need to have patience for any of this to work. It may take awhile to adjust, but with patience, it will be easier.