Multi-Patterned LED Flasher Program for Microcontroller / PIC

I need a program written for a Microchip brand PIC 24FJ64GA002 that will flash 16 LEDs in multiple, selectable patterns. I have a circuit board already designed and will provide you with the pin outs for the LEDs and interrupts that you will design the program around. I will need the source code files, plus all necessary files for me to program the PIC using ICSP with a PICKit3, including but not limited to the linker file, etc. The program will need to operate as follows: The PCB has 16 LEDs, 8 facing front and 8 facing rear and a 9V DC power source. There are two momentary push buttons, one controls the front and the other the rear LEDs and they operate independently (front and rear can display different flash patterns). Each push button will operate the same: when the LEDs are off, a quick press of the button will activate that group of 8 LEDs. When they activate, they will flash in the last pattern that they were flashing in before they were turned off. Quickly pressing the button a second time will advance that group of LEDs to the next flash pattern; each time its pressed in this manner it will advance to the next pattern. When it reaches the last pattern, the next push will start back at the first pattern. Pushing and holding the button for 1 to 2 seconds will turn that group of LEDs off. While the LEDs are off, pushing and holding the button for 3-4 seconds will place that group of LEDs into "demo mode”. Pushing and holding the button again for 3-4 seconds will take it out of demo mode and turn the group off. "Demo mode" will have that group of LEDs cycle through each pattern one by one for 15 seconds per pattern. For the flash patterns, the front 8 LEDs will have one set of flash patterns and the rear set of 8 LEDs will have a different set of flash patterns. The flash patterns will simulate various strobing flash patterns that are used on police and emergency vehicle roof lightbars (search YouTube for Whelen Liberty and Federal Signal Arjent for examples of the types of flash patterns that you will need to design). I will supply more specific patterns, but a keen eye is needed to duplicate these flash patterns as closely as possible in this program. I will need 8-12 patterns for the front group and 8-12 patterns for the rear group - so up to 24 different patterns. Bare in mind that each pattern will be relatively short in design (lasting only a few seconds and then repeating continuously in a loop), so extensive code writing should not be necessary. Since this is a relatively simple and basic design project, I am estimating $20 per flash pattern x 24 flash patterns to a cost/budget between $200 and $250 for this program, though the lowest will get it and again, this pretty much beginner level stuff so I'm sure someone will be willing to do it cheaper. What I do ask however, is whoever is awarded this project to first send me a "test" program that is one simple flash pattern (your discretion, I just ask that it utilizes all 16 LEDs and does so one by one to demonstrate that you understand the project and the LED pins are correct) that I can program into the PCB (this will also ensure that the PCB is working properly and will accept the files you provide). If it works, then we can get into the real work of designing the actual flash patterns. Also, this is only the first of several projects like this, whoever is selected will likely receive additional work (if you want it) and more complex LED flashing projects that will pay more then this one.