If you can rent 3 units for $2,000 you are close to breakeven.On the plus side, you will have a highly attractive asset and several decades without much cost of capex and repairs. 

You're using a company to manage tenant phone calls/inquiries and then send in vendors for repairs.

The $100-$300/month amount is just a generalization - but the point is, on a monthly basis you don't see a huge income per property - and you also have to absorb repair expenses and such as well.   

A lot of wholesalers lock it up at 75% - repairs and then try to move it at 80% - 85% - repairs.

.- This will allow low down payment and the 203(k) allows repairs to be financed into the purchase mortgage.- The 203(k) will allow you to bid on properties that need repairs that won't qualify for a traditional mortgage => less competition => better purchase price.You will need to find a great local contractor you can trust to supply the required bids to qualify for the 203(k).- After closing, you can do some of the work yourself to save money, but the program doesn't allow you to pay yourself.You will want to buy a Class B property, maybe Class C+, in an area that seems to be improving.

I use $2500 to pay expenses and save what's left in a fund for repairs etc...So I can count on approx 5K/month in gross income. 

The government will clamp down on the abuses and chill the technique, ruining the use of Subject To.

Well even if the rent is equal to the mortgage, you'll still be in the negative after repairs, CapEx, vacancy, etc.Why would you specifically be thinking of investing at a negative cash flow?

Each of the 5 warehouses on this campus will require updates (construction of offices/bathrooms, roof repairs, paint, siding repairs, new penetrations for doors, updates to electrical, insulation, and extension of water and sewer). 

How much will you spend in repairs on a 1920's house with renters ?