Small vs Larger blocks of units

Any thoughts on which is best - the pros and cons of buying into, say, a block of 4 units compared to a block of 17?

I'd go the 4 pack.

Personally I'd steer clear of things with too many of the same thing in them.
- no uniqueness = lack of future demand if you need to sell
- what can you do to get more rental from yours?....nothing :(
- some fire sales in the complex = your unit valuation drops (comparable sales in the same address)
I have units in developments from 7 units to 84 units. It is much harder to get anybody to agree to anything in the larger blocks and the AGMs usually turn into personality issues.

Now I would be of the opinion of the smaller the better, especially if you own two or three and then you have a real say in what goes on.
I'd go for the smaller one too.

Generally, smaller complexes don't have lifts, pools, gyms etc and so strata levies should be lower.
I prefer smaller groups, too and try to find a better than average land ti building ratio.
The smaller groups also give you the opportunity to buy all of or a controlling interest in the entire group. Harder to do if there's 20 in the complex.
Any thoughts on which is best - the pros and cons of buying into, say, a block of 4 units compared to a block of 17?
The only items to look for is the land content,and future zoning,and "Loation",i look at it like this you can buy without any agents in inner Southside Brisbane,old weatherboard queenslanders split into 3-4 one bedroom s/c BBC res flats,on above 1000s'm lmr zoned land for under 600k
the return is not that important, but longterm if BBC change zoning for those blocks,which they will under the new planning laws,then something like that can go above 20 levels from a run down property..
i bought one like that 3 weeks ago from a simple 2 lines add in the local paper,private sale,the vendors not only lost money over the last 2 years and just had a gut full on running a run down dump with a very high tenant turnover and police and council proplems:),just depends on the way you think..and you won't find deal like that talking to flash in the pan real estate agents,
I would also go for a smaller complex... recently wanted to buy a brand new unit - one of the banks had issues with it being a "high density property"... another bank valued it way lower than the purchase price. Glad I pulled out. Agreed that there is no uniqueness.

Now finally decided on a villa in a small complex...

So I say smaller the better.
We have owned units in complexes ranging from 8 units to 80.

It is usually more economical to go small or large. Go for a 4-6-8 pack with no facilities, pool, etc and only basic landscaping. Or go for a big complex if you want the pools etc, but be sure to steer clear of lifts (expensive) and gyms (legal issues).

Avoid complexes of 25-40 with facilities like pools, lifts, gyms or resident managers - you will be paying a large chunk of your BC payments to fund the manager, and there are fewer to share the other expenses with.