Another good thing to do is practice scion cuts, thats a real important part of grafting. And remember, a cleft grafted mango will take about a year to look anything near a three gallon.. I try to save the rootstock for mangoes that arent readibly available in 3 gallon size. To me a seven gallon tree is worth a lot more than the market price, unfortunately "common" people see it differently. When you actually graft a mango and grow it to seven gallon size you truly can see the amount of effort and time involved to create such a tree. I would guesstimate that a seven gallon mango tree grown on small scale (1-20) would cost someone more than $150 when you factor in the seedling nurishment (water, fert, space, time) followed by grafting time (scion collection, grafting materials, time) followed by aftercare (materials, time, stress of watching, failures), followed by stepping up to next size (soil, pot, fertilizing, watering, space..., TIME), followed by stepping up again (if the tree makes it this far) plus.. (soil, pot, fertilizing, watering, space, Time...) And if all goes well in about two years you will have a tree suitable to be considered a seven gallon tree worth about $60 in todays market, a market where the "common" person will feel they are being ripped off for a plant in a pot.