Free & Clear Owner Finance Possibility

I am focusing on lease options and in the marketing process other kinds of possible deals pop up. I am of the mindset to master one niche before schooling myself on others.

This came to me this week and I am wondering if it sounds strong enough to make an offer on. And if so how would it be constructed.

I made good rapport with the seller while working on another property he has. I told him I would give him an offer with a couple of options for him to choose from after I looked at the numbers.

So, here's what I have:

It's a duplex in Lake Havasu City (popular retirement & family community).

The man has a dread disease that has forced retirement and is anxious to sell this prop. He would rather have good monthly payments than a big down pmt.
I'd like to put together a win win proposal.

Owner will carry--- all that needs to be worked out are the terms. There is no loan. We can make up any dn pmt and any mo pmt.

Duplex--ea unit is 2+2 about 998 sf; fair market rent is $1000 to $1100
One unit has been totally remodeled---the other is a mess with a long time renter who is a hoarder and only pays $500;

Listed with agent who can be let go anytime;
Price is in the mid 130s

Closest comp is $165k (.24 mi)
Another within .3 mi sold for 155k
2 more comps within .5 mi range @$155-160 and are newer.

I am thinking to offer $107ish: 75% of fmv of $160ish minus 10k to remodel the bad unit and 3k for the eviction stuff (I HAVE NO IDEA what it costs to evict a tenant--I was just guessing it would take 3 months)

then:
evict tenant, rehab the bad unit for 10k, rent units for $1000.

Do you think these are good numbers? Any feed back you could give would be appreciated.

Thanks in advance!