Define "Full Aspect".
My layout has about 50 signaled blocks (80 signal heads) but it is limited to green, yellow, and red aspects on the searchlight signals. When I installed it, the Digitrax SE8C signal driver boards were not available. If I had used the SE8C I could have used 4 aspects per head. For searchlight type signals, the SE8C supports red, yellow, green, and a 4th aspect which can be flashing red, green, or yellow or a dark signal.
How can you do it? You will need detection, turnout position information, signal drivers, signals, and logic. I used Digitrax BDL168 for the detection, Digitrax DS-54 stationary decoders for the turnout position information, CTI Signalman boards for the signal drivers, Sunrise Enterprises for the signals plus some bi-color LEDs for hidden areas, and a computer with RR & Co software for the logic.
I am in the process of designing a signal system for a local model railroad club. I don't know the block count but we are looking at about 33 signal heads for the mainline. Total cost, not including the computer or the software, is somewhere around $1,000. This includes Digitrax BDL168 detection boards, Digitrax SE8C signal driver boards, and the signals. I won't need Digitrax DS54 stationary decoders for this installation because the SE8C boards have 8 turnout drivers per board.