You are sitting in a large very tall building, someone has instructed you to get the windows cleaned! Where do you start? Are you currently situated amongst other similar sized buildings? Ask them who they use and have if they're happy. Or even, then as always the answer will be a click away on the ever dependable Internet.
Type in Commercial high rise window cleaner or Rope Access window cleaning along with the name of your city or location. You will usually find a very good service providers could have the best & most professional looking websites. I say this as you are certain to get many companies getting themselves on say page one of Google through computer know how and not investing in a quality website, which denotes effort and a will to be successful by doing things correctly, which in turn you might have thought will be a general reflection on how they conduct their business.
I would select three or four companies, this is not as time consuming as you think since it will be the potential contractor that may putting in most of the work. If High Rise Window Cleaning Lower Sydenham have made your decision, call each company and give them a small amount of information about your requirements, for example the size of one's building, how many floors, whether you'd in mind external clean outside only, both sides, internal partitioning, special attention to the reception area, managing directors office, boardroom etc what sort of frequency you initially had at heart. This is a thing that you can both discuss at a later stage. A good contractor will recommend a reasonable frequency, one that will be designed to suit your organization and image requirements rather than to get just as much money out of you as possible. Inquire further for feed back, you can usually get yourself a positive feeling for the sort of person or company your coping with this initial chat. Remember, you have not committed to anything so try and get as much information as possible, this could save you lots of time further on.
Ask how they treat Health and Safety, you can usually get a good idea from the sort of response you receive. An organization with an excellent Health and Safety record will undoubtedly be very vocal relating to this. You will then be looking to arrange for site visits. Now for me, this is the the most crucial section of the arrangement. From the contractors viewpoint, he cannot have enough information, especially if we have been talking about an extremely large building. I know you don't want to be spending plenty of your valuable time with this but believe that's where it is possible to save so enough time by being precise in your instruction and requirements making sure your potential contractor has as much useful information as he needs. A genuine big aid is a computer graphic of all the elevations of the building or photos if that is possible, I know this is simply not always the case, I'm just saying this makes everyone's life so much easier. You can both make reference to it at any stage and it's there in monochrome. Even an architects drawing, providing it gets the windows included is simply as useful.
Finally, all that remains is for the contractor to provide you with a price, comprehensive method statement and risk assessment and for you both to agree on frequency and terms and put a contract set up. Please be aware that if you agree to pay earlier you will be entitled to a discount. This is something I like to offer as cashflow is key. After all, if your contractor offers you a top rate service and does everything in the timescale you have agreed then by paying on time or a little earlier could benefit both parties.