This could limit how quickly I'm able to build a portfolio of properties. 2.

There are some real advantages w/scale and a concept called forced appreciation (value add approaches) that make large apartment investing attractive.  

If you don't have a RE agent, I would either google for the top realtors in your realtors and start calling them.And/or search for realtors on BP to help you.When I need a quick search online, i use findcompsnow and realquest express 

How quickly are houses selling in that area (average days on market)?

What to Look for in a Real Estate AgentWhen buying a home, you want a real estate agent who… Takes the time to understand your needs and goals, so you have a true partner in your home buying journey.Explains everything clearly and answers your questions, so you’re never in the dark.Has expertise and a track record of success in the local market.Knows how to find great properties in your price range.Will alert you to new listings, quickly, so you get the jump on those opportunities.Will advise you on the best price to offer for the home you want.Will prepare and present the offer, and skillfully negotiate such things as price, conditions, closing dates, etc. so you get the best deal.Will save you potentially thousands of dollars by ensuring you don’t overpay for the property you want.Will recommend reputable home inspectors, movers and other professionals you may need.Not every real estate agent offers all of these services.

I have been too lenient. Tenants are very messy.  They have received a city housing violation.   I told them about it in advance (it's also left at premises by code enforcer).  They did not correct in time so I got th...

Both markets seem attractive.

I wouldn't settle on the front-end if you're investing from overseas... too many variables that will turn this one sour for you quickly. 

I'm seriously considering this single family that needs renovation in a terrific area and need to act quickly.

How quickly are you looking to close?