I would request the experts to please educate us on where to start and what are the steps that we have to follow.We are talking to couple of Engineers and General Contractors to get more information to see if the project is feasible.

As a matter of fact I've been toying with the question of whether it's feasible to do enough business in a single neighborhood.Anyway, to answer your question my top qualifying question is: "Are you willing to sell the property for what you owe?"

I know there are a lot of details but I think it is important to know how much I need to allocate for such a deal if those two financing options were feasible.

That gives you a much longer feasibility period to determine whether or not you want to continue with the contract.The one thing I've seen over and over is when there are long-term tenants, they are always paying well under market rates.Whether or not there are written leases, you should always ask for estoppels.

what has changed that this would even be a consideration, You don't have to say yes.. if it's because the house is no longer feasible to suit there physical condition, due to access or other features I may agree to looking but the funds can also be used to remodel and upgrade current house to fit their needs. 

How much should I be paying just to have them work out basic feasibility plans as well as get a simple bid to GC it all?

Ask the interviewees what their thoughts are on your timeline, budget, and feasibility.

It is not common but it is very feasible.

Zoning, utility connections, natural hazard zone reports, feasibility studies, construction costs and soft costs are all hurdles and you need to know your market.

Homes in my area of southcoast MA are pretty expensive so putting down 20-25% for a down payment is not feasible right now.