At Dermarta our team have created many, many bathrooms. Designer ones, ensuites, shower rooms, mosaic themed bathrooms and plenty of basic bathrooms.
Generally we have a fixed price for each of the set processes of dismantling an old bathroom, plumbing, tiling, decorating etc. The cost of purchasing a bathroom suite can vary enormously depending on taste and budget but the pipework, tile glue and grout and the skip to take away your old bathroom will cost the same!
The best way to get started is to get to a decent bathroom showroom. You may as well start at one of the fancy ones to get a few ideas and then you can either get out your credit card or go to one of the big chain retailers such as Wickes, Homebase, B&Q, Bathstore. The alternative is to trawl the internet. There is a massive choice out there and prices are very competitive. At Dermarta we have very good trade discounts at various builders merchants to help keep building costs down.
The overall cost of your bathroom will depend on may things besides your tastes. The size, repositioning of plumbing, tile coverage on both the floor and wall, the source of hot water etc.... Will you need new spot lights? An electric shaver socket? Will you let the steam out the window when it's snowing outside or will you need an extractor fan? There are lots of ways to spend money.....or save!