Andy,
I think it all depends on which area of the country and how wider area you cover & how well you know your customers. We always give a written quote prior to works which clearly states our terms which are 14 days from invoice date afterwhich interest charges will be added. Most companies will only pay on presentation of an invoice and after a period of time, usually longer than you would wish, thats why I always allow for this predicted wait by adding more to the quote.
My domestic customers 9/10 usually pay me a cheque or cash after the job is completed, but they still require an invoice to be presented and a receipt for obvious reasons. Unless I doubt my customers ability to pay when estimating, I will usually send an invoice & not expect payment straight away. This also gives me the oppurtunity to include further advertising material, discount vouchers etc if needed.
Like I said everywhere is different. I live on an affluent Island with many wealthy people, so payment isn't normally a problem. I don't know about your area, you may need to ask for payment on completion and ensure the custy understands this when estimating. Still produce an invoice along with business card etc, it looks professional.
Unless your a big company, excepting credit cards is in my view is an overhead too far. You have to pay a monthly fee for the machine plus a % of money going through the machine if I can remember rightly.
Regards, Andy