Maybe you might also want to do a combination of the three.

Very true  Roy NAs a starter I would think -- a combination of flipping with rentals would be good, till one can establish oneself as a wholesaler.

The three northern territories (Yukon, NWT, Nunavut), while they comprise almost 40% of Canada's geography, have a combined population of <115,000.The Atlantic provinces (NB, NS, PEI, NFLD) have a population <2.5 million (fewer people than the City of Toronto).The Prairies are about 6-million in population.BC is about 4.6 millionQuébec is ~ 8 millionOntario is ~13.75

She has an agency of 3 agents, with a combined experience of over 95 years.  

Usually this criteria is combined with length of time required to recoup their original investment, typically 2-5 years. 

In particular, if there was a preferred return and let's say the investor put in $400k, got $300k back via preferred return so far and an additional $150k back as share of remaining cash flow over the years (so he actually got $450k back in aggregate), and there is a profit when the asset is sold, would you first give the investor $100k (the remaining portion of his capital not paid via preferred return) before splitting the rest of the sale profits according to what was agreed, or would you consider that the capital was already returned (as he got a combined $450k), and proceed directly to splitting the proceeds of the sale?

There is now way to combine the payments into one.

Every partnership has these two aspects in a vast variety of combinations as to what each partner will contribute.  

I'd be surprised if your vacancy and maintenance combined are only 10% for the long haul.

In my experience a partnership can be an excellent way to combine complementary strengths in order to realize a shared vision.