Also, go to the county recorder's office & record your lease. That protects you from some buyer saying he didn't know you had a lease. Some people do buy houses with sitting tenants. It lets them get used to being landlords before they have to try their hand at advertising & screening new tenants. If L wants you to leave, L has to bribe you. Make him pay at least 3 months' rent + moving costs. L can't sign a 2 year lease then say you have to leave because he doesn't own the place. The place was empty, it belonged to his mom, he was clearly her agent for purposes of managing the house, and his signature is binding on her. She can sell but you get to stay.
Also, send the real estate agent a letter that you need 24 hours notice before the house may be shown, and you must be present for all showings. Tell the agent the hours you will be routinely available. Also tell A that you'll sue for abuse of access if A violates these conditions. Don't take off work just to show the house unless L is going to cover your wages. In the letter, tell A that you want to attend the closing to make sure the damage deposit & move-in checklist are transferred to the new owner properly.
Finally, look up your state's residential landlord tenant act section on landlord's duty to maintain the premises. It will tell you how to notify L of needed repairs so that you can sue L later for not doing them.
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This is not legal advice and you are not my client. Double check everything with your own attorney and your state's laws.
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