before i joined up thats what i did as a job (amongst many) stealth installs of AV systems,most LCD projectors have a 10,000 hr life for the bulb, less if you smoke and thats if you clean the filters properly, sky box can be conected no probs, any other devices can be conected, and AV amp is recomended as the speaker on the projecter will be poor no matter what the make, a Yamaha or a sony es range amp is good for low dosh if you are spending money then there are ooodles of amps but the two amps above will do the job, big money says KEF thx series speakers, lower price then your buget is your guide. for a bracket use unicol for the projector, as for wirless conections its not worth it as the projector is a monitor, you need 2 cables to it at most, a composite conection and a SVHS cable, if you are going high end then you need another 3 for component video (RGB)(avoid projectors that advertise that they are scart compatible)
if you need any other help just PM me and i will do what i can