Hiring a forestry mulcher is the most efficient way to go about putting in any new trails in terms of money, efficiency, and time. I understand people will look at the price of a good operator expensive at $250-350 per hour, but it is definitely worth the cost. And just because "I know a guy who can do it cheaper" does not mean it will be the quality you expect. Remember you already have a list of items that need to be completed on your property at any one time, setting some money aside and research a good reputable company to do this is worth it, trust me! Call up a few guys, ask some farmers, or neighbors and get some leads on who to contact. Get their rates, their experiences, and references so you can double check their work. If you like the results I would get on their list as soon as possible.
Once a trail is blazed in, it will be much easier for your equipment to disc it and start working the trails to either be converted into food plots, or just easier to walk/drive down. Check with your local SWCD/NRCS/DNR if you have a management plan already in place, you can usually get this to be cost-shared by building it as firebreaks, timber access trails, etc. Most cost-shares will cover up to 70% of the cost of a project. You will need to have DNR Forester set up the project, you will get the contractor, and when the project is done, they will review it and make sure it was done correctly. Afterwards a check will be mailed out to by either that agency or your states Department of Revenue for the amount to be cost-shared.
With older equipment, though it is cheaper it can be more of a hassle than time/money saving. I know from experience buying older logging equipment and older skidsters, I thought I was saving a lot of money, but rebuilding engines and breaking hydraulic lines especially in winter, got me thinking. Once I got into a cab of a ASV135/Bobcat590 or even a dedicated Fecon Mulcher, that worldview changed. I mostly rent the machinery I need to do forestry work nowadays for specific jobs, and if I can't do it, I find someone from my contractor list who I can trust to do a good job.
Move on to the next project and save your time and back.