10% is what I charged if I was billing for steel and consumables

I never mark them up but I always get p.o. number and go get it or have it delivered if I buy I do mark it up a little but not much just to cover the extra time it will take when doing sales and income tax

I had one customer that I did allot of work for.. He was a pickle to deal with.... I would mark up material 50% on him...

If I am bidding a job I try to make my material and labor cost be the same... So $500 labor $500 material... $10,000 labor $10,000 material..

If one cost or the other would get too far out of wack I would ether turn the job down or try to figure out what the problem was.

That system worked well for me for ten years..

25-30% if you have to buy material consumables are figured in your labor cost and that price depends on the area you live in around here in south Texas its 60-75 an hr

Materials should be marked up 15% minimum plus your margin and consumables your overhead plus your margin.
If you are not, you are giving away money.
If this is a $1-2K job and you get paid as soon as the work is finished and you are a "Nice Guy" then maybe you can afford to front the materials and consumables. If you have a $250K materials and five welders going through $7 dollars a hour consumables ($350 per day per crew) and the customer keeps you 45 days out, then your durn well better marking up your materials and consumables. They will eat into your profit quick.

That's a tough call for me. On some stuff I've marked it up, other things I don't. Usually it's figured into the price. Figure out how much material costs, what the job is worth and there you have it. Seems when I first started I was more into figuring the exact cost of materials, then adding 20%. Now not so much. A friend and I bid a job after talking on the phone for about 10 minutes, didn't even know how much material was going to cost. Knew how much we needed but that was it. This last year though I really have not even thought about markup. The last job I did 165' of fancy rail with about 100 feet of radius railing and I had no markup on the material.

You do enough of one thing or types of work and you'll have an idea of price when you walk onto a job.

Selling steel at the shop it gets marked up 60% for whole sizes/lengths, 100% for cut lengths.

When being used on a job, it depends upon the size of the job and the attitude of the customer but at least 15% to cover handling, ordering, paperwork, etc.

Don't give time away.  Check what electricians get when they come and replace a part at your house or business.  Same with plummers, etc.  None of them sell you the part for the same price they paid for it.  And they charge you driving time to go get it if they don't have it on their truck.

Have a Great Day,  Brent

30% is reasonable.
Remember you put in time and backbone to find, receive, handle/unload this material.
YEP, you could have had your hood down.... So what is the difference?
Or did the Material Purchasing Fairy place this stuff on location for you???