Finding costly defects (in roofing, plumbing, electrical and foundations) after the fact may turn the transaction into a breakeven deal, or even a loss.

I am an investor in Clearwater, Fl from NJ, one year ago, I purchased a property in Clearwater, I surprisingly found out there is a large garage in the backyard have existing plumbing and electricity in it, also I can tell the previous owner have already turned the garage into two bedrooms in-law suite, but they cover all the things up for selling process, so I wonder 1. if necessary to invest more money to upgrade the garage into an in-law suite, so I can rent out to one or two tenants for extra cash 2.

As of today, I have rehabbed 5 of the 6 units (which are all rented out at $1200 a month) and I have to build a laundry in the basement and take care of some minor plumbing work and porch reinforcement (this will all be completed by July 31, not sure when the last tenant will be evicted).

Use your inspections to check all the systems of the home -- foundation, roof, plumbing, electrical, and HVAC. 

I need a referral for a GC for a HomeStyle Loan who can do/oversee plumbing and flooring on a foreclosure.

Depending on how the layout is changing, ensuring that no load-bearing walls are being moved, and also if plumbing fixtures are being added (which it sounds like there will be) you may need an Architect.

Here are the things we keep an eye out for when it comes to renovations:  (1) major components go first - roof, electrical, central air, plumbing, (2) plan, plan, plan... 

@Samvel Gevorgyan I use all hours plumbing.

The garage already has plumbing, it's own yard area and enough height for a loft. 

This means a rental unit that:o Is secure, with doors and windows that can be lockedo Has working plumbing, hot water, heating, and at least one smoke detectoro Has functioning electricity without unsafe wiring or outlets.Your landlord must tell you about any known lead-based paint or hazards.Your landlord must keep any common areas and elevators in clean, usable condition.You have the right to basic privacy in your home.