Of course they have already found suitable properties.

First and foremost does the applicant have suitable income to afford the apartment?

I would encourage you to discuss with your dad what returns would be suitable for YOU.

I am a building contractor interested in building a multi family building between 4-8 units in size.Can anyone offer advice on where to locate vacant land suitable to build on?

Higher interest rate forcing us to pay more into debt financing hence adding more cash is suitable.

Take your tax free 130k and invest it in a more suitable cash flowing property. 

Also how suitable is AZ state for real estate investing?

I have gutted it and am turning it into 3 condos, but am having a hard time determining what kind of intercom system would be most suitable.

If the building was suitable for some other type of business it may be a more stable source of income.

@Austin McCasland the other option is renting two rooms to one person (bedroom and office or private living room) and they have their own bathroom. each home can be suitable to Rent by the room and others are not. just my opinion