But the most important thing is TRUST and handling/ getting them used to you, being around you, even if you do not handle them, just lettting them walk around, when you are there.
And remember, some will never really LIKE to be held, may tolerate it, but may not be as you say a Lap uro.
I have to say through my own experience, with a saharan and an egyptian, the saharan knows me, is inquisitive about what I'm doing, will tolerate my handling, but would much rather not be loved up, hehehehehe !
The egyptian female , was babied and held alot, and was out walking in the room alot, she is by far the closest to a lap uro I have had. VERY trusting, sweet, and content in your presence / or on your lap. 
I like the egyptians as pets. BUT I'm sure there are also some that do not have nice dispositions , as with any animal/ hey and some people, LOL 
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PHEve/ Eve
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