For that tenant, only used it for rent collection. 

We expect to continue to acquire properties as a group.At the moment, I've been collecting recommendations on suitable attorneys. 

Meeting that 2 in 5 of the last requirement allows a single owner to shield $250k of appreciation and a married couple to shield $500k.Unless you predict a lot of income from the MTR or you feel that there is a lot of appreciation incoming over the next three years (minus time get the property sold), you may want to consider collecting your $100k (passing GO) and redeploying that money to whatever you feel is its best use. 

How much time should I realistically allot for application/background checks, walkthrough, paperwork return, deposit and first rent collection? 

While collecting payments for buyer for 30 yr's.

For collections in Southern California, try Sutton Law Center or California Judgment Enforcement.

Starting small and scaling up is a tried-and-true path, and this community is filled with people who’ve walked that road and are eager to share their experiences.Feel free to ask questions, share your wins (and challenges), and tap into the collective knowledge here.

Quote from @Jesse Turner: What, if anything, are people using for collecting guest feedback?

If there is no HOA because it has been family run, it will be dicey, but generally if it is a private road, all those on the road are collectively responsible for maintenance and improvements.

That gives them plenty of time to collect and transfer everything to you.