When I went through various versions of Pulci's life (some years ago meanwhile), there were many contradictions, I remember. It took long, till I realized the crisis between Pulci and Ficino and its importance, not every researcher had realized it. Pulci's function for the Medici since 1460 seems to have had gained its force by the condition, that Pulci's mill was close to the Medici villa-castle in Caffaggiolo. Michelozzo started in Medici commission to work on Caffagiolo about 1452/53 and 1458 it seems to have been the time, when the villa became of some use, but more for Lucretia Tornuabuoni and the children than for the older male Medici ... Caffaggiolo is about 40 km from Florence, and the Medici were often sick then. 40 km is a lot in mountain regions, especially if you don't have a good health. Careggi is only about 7 km.
That are rather practical conditions, which say, that the Medici-Pulci relations likely depended on the stays in the Mugello. But all the biographies and the Morgante versions didn't tell anything about this detail.
According to the 1989 introduction to the English translation, with extensive citations, in 1459 Luigi "entered into service as a trusted secretary and accountant to Francesco Castellani, a wealthy Florentine gentleman and personal friend of Florence's ruling family." He then met the Medici and was a frequent visitor at the Via Large Palace, Cosimo's Florentine residence.
Around 1463 something like 15 and a half canto (or something like this) were ready, and then the production was stopped and proceeded in very low steps only. Somehow this must refer to the condition, that Lorenzo had reached an appropriate age, in which he got more responsibilities, and the childish poetical experiment with "Morgante" went to the background. I've for the moment no idea, where the link to this very good research has gone to.
According to many sources, including the poem itself, Luigi started Morgante at the urging of Lorenzo's mother Lucrezia Tornabuoni, who wanted Pulci to "write a poem which, by celebrating the figure of Charlemagne, would extol all the good deeds the emperor had done to defend and promote the faith" (Lebano's introduction, p. xiv). It's like Ariosto's poem, written for Isabella. These things were written for women. He probably stopped writing because of the financial matters that caused his exile in late 1465. His brother Luca had gone bankrupt in Rome and returned to Florence--Lebano doesn't say when. There he contracted even more debts, and the creditors went after Luca's brothers, who had shared in their father's inheritance. The "exile" was only a few months. From a letter of March 12, we learn that Pulci was already back in Florence.
Matteo Franco" and "Pulci" had a fight with sonnets, which was published as a selection in 1759.
"Sonetti di Matteo Franco e di Luigi Pulci assieme con la Confessione ." This was part of the aggression between Ficino and Pulci, Matteo Franco stood on the side of Ficino.
From a letter written in February of 1474 and addressed by Luigi to Lorenzo to complain about the latest degrading sonnet Franco had composed against Pulci, it appears that until Febrary 1474, Ficino had not overtly sided with Franco in the latter's quarrel with the author of the Morgante.
Then Ficino sided with Franco, and the quarrel with Ficino began, lasting far longer than the one with Franco.
Pulci stood more for "the man from the country, who had difficulties to get some Latin together". But although Pulci's bad financial conditions and his lower stand in the society by the family debts he gained some influence on the young Lorenzo, and when Lorenzo surprizingly became a man of power, others got envy about Pulci and his close relation to Lorenzo, especially from the side of the noble and intellectual Platonic academy and all their fine words, who wished to gain Lorenzo for the high aims of Renaissance. That's also the story.
Pulci was envious of Lorenzo's growing closeness with Ficino, whom he thought over-intellectual, for sure. In the sonnets, they quarrel about religion. Pulci ridicules the idea of pilgrims going to Rome for the Jubilee. While Ficino is lecturing on the immortality of the soul, Pulci writes that there is no reward for the just,after death, nothing but a "huge, dark abyss". And the soul is just--well, I can't find the exact words, but something the opposite of what Ficino says. In his next sonnet he scorns and denies all the miracles of the Bible. Everyone in Florence is shocked. Then he calls Ficino "God of the cicadas", "Fool's face", and "Venerable Syrian owl". Ficino asks Giuliano and Lorenzo to intervene. They do so at the end of 1476. In 1479 Pulci writes an unconvincing, formulaic religious sonnet. Then comes his Confessione, the sincerity of which "is a matter of speculation" (xxi). After all, even after the "conversion" in Morgante, he still feels a spark of the Sibyl, as I quoted before.
Earlier I cited Walser's book as the most dogged but careful exposer of Pulci's magical and heretical side (including mention of a threat of excommunication). It's in German and I can't get it. It might be worth looking at.