should I do grafting?

I never grafted any fruit tree, but I read a lot of stuff and watched videos.
My situation is the following: I don't need anymore fruit trees for myself, but I sell rare herb plants mainly at a local shop. There are other growers in the shop but no one of them does grafting and I searched for someone who would sell them some trees but I did not find anyone.  So long story short: should I myself then do this? Note: I've never grafted.
1. I would have to buy dwarf rootstocks because we need to net all fruit trees in the area. For the subsequent years I would probably grow and hill the rootstocks  in beds, how close together can you plant them and how many rootstocks can you harvest each year?
2. I don't have a big enough greenhouse
3. I would probably have to grow them in pots
4. How long from graft to sellable trees?
5. Is it ethical - I mean can the tree fail several years after I grafted it? I only want to sell good stuff.
6. We are in cool temperate climate and can grow all from apples to lemons, olives.
Thanks for the advise!!

Yes, you should graft, (it is a great skill to have in your gardener basket and it is pretty easy to learn)

Once you get some rootstocks you can make more by propagation (air layering works great and you were going to cut off those unneeded branches anyway, so making use of them is good)

Usually grafted trees are ready for sale within 2 years of the graft taking, many do keep them around for up to seven years since trees that size sell for more money.

Any tree can die at any time, holding a tree for 2 years after the graft takes allows you to make sure the graft is well established.
Container growing is normal for grafting trees in the nursery setting. Just be sure to have large enough containers.

Redhawk

If growing out the propogated root stocks and/or grafted trees in beds instead of containers, what spacing is needed? Of course it will vary over time.

Here's my semi-educated guestimate at timing and spacing for this sort of thing. I'd much appreciate feedback on this, as I'm about to step up small propagation efforts to a batch of crabapples!

Draft schedule & spacing for propagating local crabapples as rootstocks (or just as crabapples!) with option for grafting:

Year 0-1 seeds: Grown quite dense, could be scattered in a seed bed ~1-3" apart. See what takes. After a year, separate and transplant...
Year 0-1 rootings: Rooting done from a mature specimen. Let the rooting take in place, probably air layering for apples.
Year 1-3 seeds: Transplanted seedlings 6-12" apart. See what takes. Healthy specimen could be grafted at year 3. Good time to keep track of inventory.
Year 1-3 rootings: Same as yr1-3 for seeds but rootings need to be separated from parent for first time, and since more advanced roots are likely, spacing should be more like 12-24"
Year 3-5: Transplant saplings 2-4' apart. Could try more grafts, see which past grafts take, track all accordingly.
Year 5-7: Transplant remaining saplings 4-6' apart. Saplings should be sold around this time as they approach 1-2" DBH and get harder to handle.

Does that seem like a reasonable plan for the spacetime of baby (crab)apple trees grown in cool temperate (zone 5) apple country?

Tree seeds would be better spaced at 3" to 6" apart for the first full year because a first year tree will put out a far more extensive root system than you might think.
Rootings are easier since you can go straight to container planting when you are ready to plant up the rootings.

Most trees don't take well to several transplants in their early years particularly.

In commercial tree nurseries when they are growing in ground they usually space the trees at 24 inches trunk to trunk, if they sprout these in a green house they plant from trays directly to where the tree will grow until lifted for sale.

saplings will do well at a 2 foot spacing unless they are subject to bush type growing (most of the crabapple in the south are bush type)

Redhawk

In a related question, if one doesn't care about tree size what are the advantages to grafting?  My reason for asking this is that I almost always have trouble with root stock suckers. One tree was so bad, I finally just took the whole thing out, and I'm still 6 years later digging out suckers.

Thanks Dr. Redhawk, that makes sense. As I considered that draft I thought it called for more transplanting than realistic.

Thanks for the replies! Yes, it doesn't seem to be too difficult. The plan is to start with apples and European plums.
I'll buy some dwarfing root stocks (because of the birds and possums), graft most of them and put some aside to grow more, either in pots or in the ground, both shown at youtube.
I think stone fruit and citrus is more difficult as well as it's done in summer when you're busy anyway.
If I graft Apples and plums in late winter, say end of August and we won't get colder than one or two below freezing could I put the trees outside right away? Maybe with an old curtain at night or under a tree??