@Bryan Thomas IF properly maintained, slate lasts a long time...it's stone...the one thing to be aware of is that slate roofs are not "decked"...they use a series of wooden slats that the slate basically rests on.

If you can reduce the Heloc payment with own capital etc you increase your cash flow even more, but remember if you are using 100% Heloc you are basically buying this house with none of your own money, so your ROI is infinite.  

It will familiarize you with the basic terminology and benefits.

The basic necessity's.

Electrical needs complete replacement (wiring, electrical box) but the house has newer roof and appliances (heating and water heater are recent), and the plumbing looks recent, which is all surprising given the state of the rest of the house...It's basically a roof and a brick frame with appliances.

It will familiarize you with the basic terminology and benefits.

What are basic questions and answers I need to have or expect.

@M Falcon we traditionally only do a set interest rate, but if you did do a %, basically, whatever their investment is as a % of the entire cost of the project (purchase, holding, rehab, misc, tax, etc) should be their ownership of the deal. 

Basically I hope to build investment property portfolio over the years hence I am looking for a good agent with whom I can build a relation.

The units are basically turn key would paint the inside and fix a couple minor things maybe 500 bucks.