While there may be forms on the internet, landlord-tenant law is nuanced and complicated. Drafting and serving notices without the assistance of an attorney is not recommended.
How to calculate the 90-day period is not always cut-and-dried. The Court of Appeals has ruled that the owner may not enter into a purchase and sale agreement and still enforce the notice of intent to sell. Meanwhile, some local laws require listing before serving the notice of intent to sell.
Landlords are strongly encouraged to retain an attorney, including for the initial notices.
Also, a generic form may not be legally effective in all local jurisdictions. Some local laws require longer notice periods than state law and/or require specific additional mandatory language. Some local jurisdictions have mandatory eviction notice forms that landlords must use.
Always seek the advice of an attorney before taking any actions that may affect your rights.
Abandoned property taken over by transient brother