I see so many assumable loan which seems like deal, but I am unable to take it as my DTI is high due to primary property etc. 

I actually made a video about this on youtube.

I would highly suggest that your father be present with the prospective applicants. 

I am considering investing in or near Orlando, Florida, in a Single Family Property, below the median in a high demand area where there are lots of people moving to.

CA has very high LLC fees so some find other ways to do it, such as LP's.

:Class A Properties:Cashflow vs Appreciation: Typically, 3-5 years for positive cashflow, but you get highest relative rent & value appreciation.Vacancy Est: Historically 10%, 5% the more recent norm.Tenant Pool: Majority will have FICO scores of 680+, zero evictions in last 7 years.Class B Properties:Cashflow vs Appreciation: Typically, decent amount of relative rent & value appreciation.Vacancy Est: Historically 10%, 5% should be applied only if proper research done to support.Tenant Pool: Majority will have FICO scores of 620-680, some blemishes, but should have no evictions in last 5 yearsClass C Properties:Cashflow vs Appreciation: Typically, high cashflow and at the lower end of relative rent & value appreciation.

But if you insist on LTR, I recommend considering areas like Marietta, Decatur, or Acworth which have a pretty high LTR rental demand right now. 

Investing is highly individualistic.

Some go for $700k plus and are designed as high end student rentals and others, in Bryan,  sell for $200k but need a lot of work.

U want your parents to talk to their CPA FIRST.. if they go the development route they are now ( depending on the amount of units) creating inventory.. which will be taxed at ordinary income rates ( very HIGH)if they just sell they can 1031  and move on to something else.. many times when you run the math consider the risks of a partnership.. the sale of the land is far better than thinking your going to make some profit..