Trade prices are usually quoted excluding VAT, which is then added at checkout. If you are VAT registered you reclaim it, so compare quotes on the ex-VAT figure.
If you're not VAT registered, the ex-VAT comparison stops being useful and you should compare on the final, VAT-inclusive figure instead — that's your real cost. Always tell your supplier your VAT status up front so the quote you get is the one that actually applies to you.
The questions are free. So is the quote.