I hope you mean brake hoses (the rubber hose). This misnomer tripped a discussion a few weeks back.
Replacing brake hoses should be the first order of business. Ideally, you should replace the brake hose, then bleed/flush the fluid from that line for one wheel before moving on to the next wheel.
I'm not exactly sure about your vintage of vehicle, but DOT 4 is specified by Mercedes. I believe the dealer sells a DOT 4+.
Definitely make sure the master cylinder never runs dry during bleeding. If it does, you may have to bleed the master cylinder before continuing your brake job.
95 E320 Cabriolet, 131K