I want to learn from experienced landlords here, how much deductible should we choose? 

In this situation we have a former-tenant  hyper sensitive to return of full security deposit (when unit wasn’t returned in good condition) and we are  experiencing a few unique damages.

AI tip 2: a friend of mine wrote an app (beta) for landlords to market themselves on a regular basis by soliciting reviews from tenants.

They will show the property, send applications, review them, and review the applicants with you, and draft a lease and any necessary local docs needed for rentals. 

I reviewed the SB9 legislation, and it states that properties occupied by a tenant in the last 3 years are excluded from SB9 but only if the project includes demolition or altering more than 25% of the exterior structural wall.

I think every house has probably experienced some sort of water damage at one time. 

They partnered with an experienced realtor who handled most of the contractor coordination while they focused on financing and design decisions..

This could add some credibility to your reviews and recommendations.

On the other hand if they are a sponsor that is experienced in stopping a skin in the game, that's a huge red flag for me.c) how open to scrutiny are they?

@Lenny MontesanoJoin local REI meetups or groups to connect with experienced investors who can mentor you. https://www.biggerpockets.com/forums/521I have found all of my best connections at local meetups.I agree with @Benjamin Aaker that it may be best to wait for steady income.