If that's the case surround yourself with individuals who give you conservative numbers, estimates and extended timelines. 

With lease expiration it is normal as with any, you serve notice and communicate that not extending lease, setting move-out inspection and all that fun. 

Since the home started out originally as a single, the 2-to-1 conversion was authorized, a kitchen was removed from the second floor and a new ADU was then built to house extended family.Your research might show that one of the 3 units was not clearly built with permits. 

Some landlords lost 50‐100% of their rental income for an extended period of time because tenants were allowed/ encouraged to stop paying rent during the pandemic. 

It's my understanding that you are not required to accept rental assistance unless you've actually signed something agreeing to the terms.I would contact the tenant and let them know you are not extending/renewing their lease.

Also with the moratorium in LOS ANGELES CITY THAT HAS BEEN EXTENDED UNTIL 2023 is scary. 

.* You will also need to ask if it has utilities, or you will need to extend them* You will need to check the zoning to know the setback, FAR (Floor Area Ration), and hight requirements* You will need to check if it will be sewer connected or Septic*....Reach out if you have any questions!

My tenant will be staying for 3 months and most likely will extend.

Your current lender should be willing to work with you on this as far as moving the closing date back and extending a rate lock (if necessary), in my opinion, in effort to remediate the situation. 

As others stated, extended your network and letting everybody know what you are looking for can help.