I appreciate why people would be attracted to the cheaper option, but as a business director I genuinely can't see how a business could, or would want to, do WECs for under £10. That £10 has to cover an awful lot! Slides, solutions, microscope repair and servicing, capital outlay, postage materials, postage costs, all the usual bills for a business (heat, light, water, rates, rent), VAT (I assume), wages, computer systems, staff training, reporting and recording, giving advice to clients, website fees and maintenance, commercial waste disposal... We stopped doing ours in-house as we found that even for the £9.50 that we charged it just wasn't worth it.