BEST
No sewer/drain line
Sewer/Drain line along back
Sewer/Drain line along back with Manhole
Sewer/Drain line along side no manhole
Sewer/Drain line along side with manhole
Sewer/Drain lines along back and side with manhole
WORST
Always worth checking Sewer does get to a property you are targeting to buy and sub divide (dial before you diag website best place to check fast and for free - www.1100.com.au), however your question can only be answered by what sort of sub division you are doing.
GREEN TITLE - you need The Minister's Line to connect to each Green Title Block you are creating, any extension to the minister's line you have to create is reasonably pricy (I'd rough cost it at $1k per metre), as engineers need to be involved with design and certification.
STRATA TITLE - As you can just split the existing connection, it is almost academic where the sewer line is, just as long as one does pass connect to the property.