I know it usually needs to go through inspection, appraisal, and loan approval.What are the realistically fastest time frames for getting this done as fast as possible?

@Tyler Mullen"application for financing shall be submitted to the lender within X days"His did say that and the buyer did make application within the time frame.

Of course appreciation is never guranteed and at times it can go backwards, but if you look at a 30 year timeframe it becomes a bit more predictable.Think of it this way: when you buy a new house, you should have 30-40 years before you have to start spending (capex) money on it.

If you don't raise the rent at this juncture and/or offer a new lease/rental agreement with better terms, they are likely to agree to abandon the old agreement and enter into yours right away.Set a reasonable time-frame for periodic "maintenance" inspections. 

You still have to sell your old properties in a compressed time frame but this time you know the property you want to buy is waiting for you.3.

In your description of the deal, I didn't see what repairs you plan to make or your estimated budget and timeframe.

I asked the insurance agent to shop around for another policy in hopes that another company won't do the inspection at all or will just require some inexpensive repairs.

Does the buyer pay insurance, taxes, maintenance, everything over $500 in expense etc.  

If you live somewhere inexpensive, maybe you can half that and only need 15 units to live on.

So I responded to all with a short email saying the property was available and asked that they tell me a little about themselves like employment, timeframe and why they are moving and we could set up a showing.