How can the idea of giving a certain service on internet be protected?
Ideas of this type do not have a particular form of protection, as they usually are commercial ideas and, therefore, cannot be patented and will only make profits if they are actually achieved.
Unfortunately, in order to be able to realise your own idea you must find someone who will help by financing it but the project would have to be exposed to them, therefore there is a risk that the same would make it without recognising any reimbursement. The best solution could be to find finances by very trusted people, even though it is always convenient avoiding showing an idea without taking certain precautions. The first thing to do is choosing an appropriate name for that kind of product, and register the Internet domain for it in your name, so to have a winning card on your side that could be used in the negotiations. If you sell a product called “prettyhouse”, you need to register the domain “prettyhouse.it” which can be done at a low cost. Having the ability for it, you can also develop, at least on paper, the manner in which you want to set-up the site, by drawing it, foreseeing the modality of payment, the kind of offer and organising the procedure of trading to be activated on the web. A copy of this documentation, which must be very comprehensive, can be put in a sealed envelope and sent to yourself without opening it, in order to supply a proof of actually having been the author, just in case of any problems. At this point, in negotiating with the people giving the finances, you could show the project without any worries, without getting too much into details and asking, at that stage, to have a contract drawn up where the shares of the profits can be provided in your favour, in case of acceptance of the project. Only after this has been signed the whole project can be presented, complete with all the particulars.