My father is looking into doing this in a cabin they recently purchased but was asking me about the quality/validity of using this company rather than purchasing new to update the bathroom. 

I decided that I would refinance using the BRRR method and use this property as my first rental property.

On flat roofs you have to look at poles, HVAC etc. attached to the roof.When contractors do not install properly they can leak from the bolts put in the roof, bad flashing,etc.Flat roof you usually get core samples to see the quality underneath the most recent layer put on.

I believe this method is good to acquire multiple properties that will be paid down by your tenants.

So I've not had many HOA hassles, and few evictions because the tenant quality is good. 

I have the goal of financial independence, and I'm considering methods of getting there.

Length of the primary lease term, level of lease guarantee, location, quality of tenant (national,regional,local) plays a part.There are many different types of lender (local,regional,national banks, insurance companies, CMBS, conduit, credit unions, private family office lenders,etc.) each has their own criteria within the space to do a loan on a property.It would take me many hours to write a response explaining all the variances.When people become my clients I already have the retail commercial attorneys, capital markets lenders, on and off market database of properties,etc. 

That will generally dictate area, property size, tenant quality type (national,regional,local,etc.).ICSC has some great books on retail.Hope it helps.

What is your preferred method for taking control of a property with a first position lien?...

The biggest issue is like what @Hadar Orkibi stated above with smaller deals- quality property management.