“How much did your build cost?” produces misleading answers unless the base van, free labor, sponsored parts, existing tools, taxes and unfinished work are disclosed. Build a budget that can survive contact with your own specification.
Keep four accounts:
- van purchase, tax, title and registration;
- mechanical baseline and repair reserve;
- conversion materials and contracted labor;
- operating setup such as insurance, security and storage.
Practical conversion-only planning bands
These are illustrative 2026 planning bands, not quotes or national averages.
| Project | Typical scope | Conversion-only allowance |
|---|---|---|
| DIY weekender | Insulation/lining, modular bed, basic 12V, portable kitchen/water | $6,000–$15,000 |
| Capable DIY tourer | Fixed cabinetry, lithium/solar, heater, fan, installed water and fridge | $18,000–$45,000 |
| Professional/premium | Design and labor, advanced systems, premium finish, bathroom/seating options | $45,000–$100,000+ |
A pop-top, approved passenger seating, large inverter system, air conditioning, indoor shower or high-end cabinetry can move a project between bands quickly.
Build the estimate by system
| Line | Include | Often missed |
|---|---|---|
| Design | Measurements, drawings, weight/electrical plans | Rework after early purchases |
| Openings | Windows, roof fans, flares, sealants, labor | Interior trim and leak testing |
| Shell | Insulation, floor, panels, furring, adhesives | Curved-wall waste and fasteners |
| Electrical | Battery, solar, alternator/shore charging, inverter, distribution | Cable, lugs, glands, breakers/fuses, tools |
| Plumbing | Tanks, pump, pipe, fill, drain, sink, heater | Mounting, winterization and gray-water handling |
| Climate | Roof fan, heater, ducting, AC if genuinely supportable | Fuel pickup, exhaust, controls and commissioning |
| Furniture | Sheet goods, framing, hardware, finish, mattress | Slides, latches, edge banding and upholstery |
| Safety/finish | Alarms, extinguishers, lighting, trim and secure storage | Many small repeat orders |
Use the US electrical calculator before pricing power. A 12V refrigerator and device charging create a different system from induction cooking, electric water heating and air conditioning. Size energy demand, charge sources and cable protection together.
Labor, tax and shipping
Professional labor rates vary dramatically by region and discipline. Compare written scopes, not hourly rates alone. Ask what design, project management, cabinetry finish, upholstery, commissioning and documentation include. State and local sales tax treatment can differ for parts and services; use the actual quote and jurisdiction.
DIY time still has a cost. Estimate design, sourcing, templates, fabrication, installation, troubleshooting and rework. Add tools and workspace. Contract work whose safety consequence exceeds your ability to install and verify it—commonly structural openings, travel seats, fuel-fired heating, propane and 120V systems.
Shipping large windows, tanks, sheet goods and batteries can be material. Freight damage and return restrictions deserve a line, especially when ordering before the design is final.
Normalize professional bids
Give every builder the same requirements document and ask each proposal to show:
- base scope and explicit exclusions;
- named major components and model families;
- design revisions and change-order rates;
- tax, freight and travel/delivery treatment;
- deposit and milestone schedule;
- expected start, duration and delay terms;
- testing, manuals, diagrams and warranty responsibility;
- whether customer-supplied parts are allowed and who carries failure risk.
A $55,000 estimate excluding electrical equipment, upholstery, tax and delivery is not cheaper than a $65,000 complete bid. Compare the delivered, commissioned specification, then assess builder communication and aftercare. Use the US builder directory to form a shortlist, not as a substitute for references, contracts and due diligence.
Three worked examples
Compact DIY weekend van: $11,500
| Area | Allowance |
|---|---|
| Shell and ventilation | $2,000 |
| Modular furniture and mattress | $2,300 |
| Basic electrical | $3,000 |
| Portable kitchen/water | $1,200 |
| Tools, hardware and finish | $1,300 |
| Contingency | $1,700 |
No pop-top, extra travel seats, fixed propane or complex plumbing is included.
High-roof DIY tourer: $34,000
| Area | Allowance |
|---|---|
| Openings, shell and floor | $5,000 |
| Cabinetry, bed and upholstery | $7,500 |
| Lithium/solar/charging electrical | $8,000 |
| Heating and ventilation | $3,500 |
| Plumbing, kitchen and appliances | $5,000 |
| Tools, checks and finish | $2,000 |
| Contingency | $3,000 |
This represents two-person touring without an indoor shower or added passenger seat.
Professional four-season conversion: $78,000
| Area | Allowance |
|---|---|
| Design, fabrication and project labor | $36,000 |
| Electrical and controls | $11,000 |
| Climate and plumbing | $10,000 |
| Openings and specialist installation | $8,000 |
| Appliances, upholstery and finish | $8,000 |
| Change allowance | $5,000 |
Real bids can sit outside this example. Compare exact deliverables and exclusions.
Control the budget during the build
Maintain estimated, committed and actual columns. Buy long-lead design-critical items only after dimensions and interfaces are confirmed. Test hidden systems before closing walls; build furniture after service access is proven; buy decorative extras last.
When one line overruns, choose deliberately: simplify another line, increase the approved total or pause. Never consume contingency without recording why.
Match purchasing to design gates
Divide cash flow into gates rather than buying everything during the excitement of demolition:
- Vehicle gate: inspection, mechanical baseline and measurements are complete.
- Layout gate: bed, seats, doors, tanks and major appliances fit the measured model.
- Weight gate: estimated total and axle distribution retain margin.
- Systems gate: current, water, heat, ventilation and service routes agree.
- Shell gate: openings and hidden infrastructure are tested before panels.
- Finish gate: only then buy final hardware, upholstery and decorative items.
Keep cash for the next gate and the contingency rather than turning it into unopened boxes. Return windows expire, product revisions occur and early components can constrain a better design.
Do not finance away an infeasible scope
If financing is involved, calculate the cost and required insurance for both vehicle and conversion. A long loan does not make an overweight layout, weak resale assumption or inadequate emergency reserve affordable. Keep the ability to repair the base van after the build; a finished interior is useless while the vehicle is immobilized.
Good savings come from a smaller van, fewer openings, modular furniture, simpler water and cooking systems, and removing appliances with low real use. Do not save by omitting circuit protection, secure battery mounts, ventilation, structural integrity or documented seat installation.
Complete the whole-project number
Add the base van using the Transit, ProMaster and Sprinter guide. Add a separate inspection/mechanical reserve, tax/title/registration, insurance, security and storage. Then follow the complete planning sequence and seek written bids for the largest uncertain lines.
The best budget is not the lowest number you can imagine. It is the number that finishes a safe, usable van while leaving enough cash to maintain it.
Price the power system after sizing it
Turn the actual appliance list into connected battery, solar, charging, inverter, cable and fuse requirements before buying components.
Frequently Asked Questions
Roam Wired
Roam Wired turns campervan research into practical plans. We publish transparent guidance, a free electrical design tool and marketplace resources for UK and US van builders.
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