@Max McGuirk
First decide how much capital you have to play with, then go from there.
As for the size, there's only 2 factors that are really at play, how much it will need to be managed and how much cash flow it will produce. These 2 factors are also interrelated, the higher the cash flow the more management will be required. The more units you have will also determine how much maintenance will be required.
Your biggest deciding factor should be how much of a return you require. More units doesn't necessarily equate to higher returns.
For example:
A 10 unit, $750k property that has $120k CF with $20k in expenses gives you a 13% return.
Where a 100 unit, $7M property that has $1M CF with $300k in expenses gives you a 10% return.
In a perfect world those numbers are amazing, however, the larger and older the property, the larger the CAPEX, which can completely destroy your returns. Not to mention, larger debt servicing, higher taxes, higher property management fees etc. All these factors eventually come into play, but ultimately it's up to you to decide how much of a headache you want at the end of the day, one that requires a few tylenol or one that requires morphine.
Personally, I'd rather own several smaller properties than one large one. In this game its all about diversifying and its hard to diversify with one property.
