Case studies —
real builds, real rents, real snags.

A Cranbourne investor with a tenanted 3-bed house wanted a second income from the backyard without disturbing the existing lease. The main house stayed occupied at $520/wk for the entire project — the tenants were notified before every trade attended, and a new paling fence split the yard so the two tenancies never share space.

Once the studio met Victoria’s minimum rental standards — blinds, heating/cooling, a compliant cooktop, safety checks — the leasing team listed it at $325/wk including bills, with a pre-agreed fallback to $290 if the first open week was quiet. It never needed the fallback: a tenant applied and moved in within three weeks of listing.

Two tenancies on one ordinary suburban title now gross about $845/wk combined — and the owner’s target of at least $730/wk net across both leases was met with the bills allowance ($30–40/wk for a granny flat in this area) already priced in.

A backyard with a swimming pool doesn’t leave much room, so this couple’s block could take a 24 m² studio — not the 30 m² they first wanted. We told them that plainly at feasibility, modelled the rent difference, and they chose to build what the block could actually hold.

The paperwork ran while their main-house tenant stayed in place. The building permit landed in early October; excavation started six days later and the slab was poured on day four on site. Frame, roof, cladding and fit-out ran through spring, and the occupancy certificate was issued in late January — roughly eleven weeks of construction across the Christmas shutdown.

Before handover to the leasing team, the property manager flagged that bare dirt paths photograph badly and slow down leasing, so a $3,000 landscaping package — walkway, gravel, mulch and grass seed — went in before the first open. The studio was appraised at $250–280/wk plus bills, in line with what 24 m² studios in the Casey area achieve.

A family weighing a 30 m² one-bed against a 40 m² two-bed chose the bigger floor plan after the leasing team modelled the rent gap: a second bedroom widens the tenant pool from singles to couples and small families. The bathroom was placed on the external wall so the layout works for both.

The site came with a cluster of old sheds and a drainage easement. Every shed had to go — a half-demolished shed leaks, and nothing can sit over the easement — so the granny flat was re-sited hard against the compliant boundary line, keeping 1.5 m clear of the existing garage.

The main-house tenants turned out to be the project’s quiet heroes: they stored trades’ tools, opened the garage when a delivery came early, and worked around the bins. Slab down in late April, cladding complete four weeks later, interior fit-out through June. As a 40 m² two-bed it was appraised in the $380–420/wk range including bills.

Corner blocks look generous but carry double street setbacks — this one demanded 2 m from the secondary street plus rear clearances, which squeezed the 30 m² studio to within 600 mm of the fence in the first draft. The owner pushed back, rightly, and the designer re-sited the building to guarantee a full metre of walkable clearance on the tight side.

The build was contracted at a fixed $105k + GST on 2025 pricing, with the fence, gate and landscaping quoted separately as genuine site-specific items. The building permit landed mid-December, which is the honest reason this one took longer than most: underground services, slab and frame ran through the Christmas–January trade shutdown, and the occupancy certificate was issued in early May.

The main house was re-let during the build — construction fencing kept the two zones separate, and the tenant used the garage the whole time. After OC, the property manager photographed the studio and took it straight to market.

Not every client buys the full package. This Cranbourne owner ran the project under an owner-builder licence to control cost, with our team coordinating the permits, the critical-path items and the trades she didn’t have. The studio was designed wheelchair-accessible from day one — wider bathroom, ramp entry — which also future-proofs it for older tenants.

The single best decision was made in week one: the South East Water PIC application (the water and sewer connection approval, $386.60, with a 6–8 week statewide queue) was lodged before anything else, so the queue ran in parallel with design and permits instead of stalling the build at the end.

The main house stayed tenanted throughout — trades were booked around the tenant, power shut-offs were negotiated in advance so the fridge and cameras stayed on, and keys moved through a key safe. After the occupancy certificate was issued in March, the property manager appraised the studio at $270–330/wk and recommended listing at $330/wk including bills.

This is the case study for everyone whose block isn’t easy. A Mill Park property came to us with a sloped backyard behind a retaining wall, an old garage blocking the only machine route, and — the real killer — no electricity meter on the title at all: the old supply cable ran through the neighbouring property.

Feasibility found all three problems before a dollar of construction money moved. The power fix needs a new pit at the street (a ~14-week distributor queue), a trench and switchboard upgrade, then a retailer meter booking — so the application was sequenced first, running in parallel with design and permits, exactly like a water-authority queue.

The machine-access maths was laid out for the owner in writing: keeping the garage meant a traffic-engineer-designed ramp and cutting into the garage floor, while demolishing it needed only a Section 29 demolition consent — a permit that costs under $100 — and freed the granny flat to sit where the garage stood. Drawings passed the building surveyor’s review in June and the project moved to contract with every constraint already priced.