Evicting my mother and her husband. Do I have other options?

Update: My mother sent me $200 and said it's a shame "that it has come to this." Her husband also sent an 8x10 envelop that I believe was a picture from the past. I didn't open it and sent the check and the envelope back to them. Even though this is difficult, their actions make it easier to proceed to the next step of filing for eviction. Several realtors have recently contacted me, willing to buy my property as is and take care of removing them once I sell it to them. I am still moving forward with the eviction; I will also respond to the investors and see what they offer.

Evict them. Cut them out of your life and never help them again.

I don't believe you do have any other options, and that's ok. They need to be evicted. It's unbelievable that grown ass adults would do that to their child.
Evict them, block their numbers on your phone and don't look back.
You are better off without them in your life.
And let this be a lesson learned, so you never make that mistake again.

I have not been in your position. I guess I would never be in your position, likely due to my heart is a good deal SMALLER than yours. I would never buy my parent's home, then allow them to live in it without paying the agreed upon rental; as you say, it was a bargain for certain. I guess I would not buy my parents home in any case, because they can come up with some malarky if they are scammers--you know, "you coerced us into taking less than market value, and so on." I just wouldn't mix family business with family love. Gets so muddy.
But it was done. You were gone. You let it slide. You had a plate too full to deal with it, and it was easier to put it off.
Chickens, however, are home to roost.
You now have an attorney, a specialist. I would follow his advice and hope it goes without a further fight, then get that house up to it's former glory and resell or live in it. I hope it goes fairly seamlessly. You have nothing to be guilty about. You attempted to do a good thing for everyone and at the time it seemed to make sense. It didn't work out. You can grieve for your parents and their irresponsibility, but you cannot fix it and you cannot change it.
I sure wish you good luck and hope you will update us on how it goes for you. Tenants right vary state to state. Were you in San Francisco you would have to give them 50,000 to move along with your firstborn. So there's that. Hopefully your state/city isn't quite that bad. Good luck, Free.

Evict those freeloading ingrates immediately. Then sue them for back.
That's disgusting how they took advantage of you and your generosity.
You say they are in their 70's now and have been living rent-free for the last 15 years. My friend, 15 years ago they weren't even retirement age. They should have still been working. In fact, they should have saved quite a nest egg living for free for the last 15 years.
Evict them and have no guilt about it. You are the one who has been treated wrongly and taken advantage of not them.
Tell anyone who says otherwise to go pound sand.

Update: The 3-day pay or quit notice has been delivered. I have taken my attorney's advice and ceased all communication. Blocked them from my email and social media. California has some interesting rules as it relates to evicting people. For example, you must put very specific payment instructions in the lease. A lot of landlords say rent is due on the 1st of the month and state that they accept check, money order, etc, and give an address to send payments. This is not enough. You must also provide the bank routing number, bank address, account number, and if it is direct deposit or bill pay. If you want it sent directly to you with no bank, your name or business name must be part of the address and you would be wise to put in the lease that non-electronic payments must have tracking numbers and signed delivery confirmation, at their expense.

Due to me living out of the state, I cut and pasted the exact bill pay and direct deposit instructions from my bank and attached it to the lease with my account number, rtn, bank phone number, and address. If I had not done this, the tenant could request to make the payment in person, and the bank must be within 5 miles of the house. If there is no bank within 5 miles, they can claim all sorts of hardships and they will receive a free attorney to assist. Also, you can only ask for the past year in back rent. Anything after that must be a separate court case. The whole process is estimated to take 6 months.

The bottom line is that you should hire an attorney to draft your lease contract. Downloading a generic one is asking for trouble. I got lucky by cut and pasting the information. More to follow.

You will have to legally evict them.
There is a good chance that you will not be able to recover what they owe you.
A quick calculation they owe you $72,000.00 and that is on the low side. You could try to sue them for that but as the saying goes you can't get blood from a turnip. If they have assets it might be worth it but I would cut my losses and just get them evicted and out. That is going to be difficult enough as it is.

Replying to your response to me.

I know you realize it now, but 15 years is a long time to keep thinking they will end up paying you.😊But believe me, you are not the only one.

My GFs Dad passed years ago. The mother remained in the home and the son bought it from her because she could not afford it. She too was suppose to pay so much a month and never did. I live in NJ the #1 state in the US for the highest property taxes. (I pay over 6k a year for a 70x100 lot with a 7 room house) So now the son retires and his State pension is cut $500. He could not afford the taxes and the upkeep on the house. So he told Mom she needed to move out because he was selling the house. She moved in with a granddaughter (Mom was showing signs of Dementia) and his sister, who was living there, with my GF. Both having health problems of their own.

So, if you are paying the Mortgage and taxes, selling the house could be ur excuse to evict them. You just no longer can carry the burden. And having a month to month lease (very smart) means you may only need to give them 30days notice. Your not renewing their lease. Please come back and tell us what the lawyer says and how things work out. We learn from each other.

Glad you have a good attorney and are making progress. Personally, I can't see any other options. Let us know how it all unfolds. Learning boundaries later in life is better than not learning them at all. Detach, detach, detach!

Yes, evict them. Also let them know that even if they don't have a planned place to go when the final move-out date arrives, they will be escorted off your property by the poliice if necessary. Also let them know that if they continue to pester you a restraining order may come their way. Don't engage verbally with them or they'll try to beg and negotiate with you. Don't. Resist. They've had their chance and now they're done. Make sure to change the locks and any keypad entry codes. Make sure their mail stops coming to your address (write "No longer at this addrress. Return to sender" on each piece and stick it back in the mailbox).

Refer them to social services for their county and Section 8 housing options.

What jerks. You can't choose your family but you can choose how you engage with them... or not. Wishing you success in getting them completely out.