How does the cost calculator work?
The cost calculator keeps track of all costs for your RV conversion. For each component you enter the price and quantity, and the tool calculates the total per category and the final amount including sales tax.
Calculation
For each line the subtotal is calculated as: price × quantity. All subtotals are summed to produce the subtotal excluding tax. The tax amount is: subtotal × tax percentage / 100. The grand total including tax is the sum of both. You can choose from 0%, 7% (state average) or 10% (higher rate). Adjust to your actual state sales tax rate.
Categories
All costs are divided across eight categories: electrics, water and plumbing, furniture and interior, insulation and finishing, climate and heating, gas, exterior and other. The category breakdown gives a clear overview of where your budget is going, so you can adjust spending where needed.
Sales tax on RV conversions
In the US, sales tax varies by state — typically 4–10%. Most materials and parts are taxable. Some states exempt certain purchases. When buying through trade suppliers or online retailers, the tax rate may differ. The tool lets you set the rate so you get an accurate estimate.
Frequently asked questions
Do I have to pay sales tax on my conversion?
Yes — most materials and parts are subject to state sales tax, which varies from 0% to 10%+ depending on your state. Businesses may be able to claim exemptions for commercial use. Check your state's tax rules for vehicle parts and materials.
Which costs should I include?
Think of insulation, wood and fixings, electrics (batteries, cables, solar panels), water (tanks, pump, tap), kitchen (cooker, fridge), furniture, heating, ventilation and the inspection fee. Do not forget tools, paint and small consumables — these add up surprisingly fast.
What does a complete RV conversion cost on average?
A basic conversion costs between $3,000 and $6,000. A mid-range build with lithium batteries, solar panels and solid finishing sits between $8,000 and $15,000. A luxury conversion with a shower, heating and premium materials can reach $20,000 or more. The base vehicle itself is not included.
How much does an RV conversion cost on average?
A basic conversion costs $3,000-$8,000 in materials. With solar, LiFePO4 batteries and a good kitchen you reach $8,000-$15,000+. DIY saves 50-70% compared to having it built.
Where can I save the most?
The biggest savings are in furniture (build vs buy), insulation (Armaflex vs professional) and second-hand electrical components. Don't save on safety: cables, fuses and gas installation.