I saw a video of Cesar Vidal and he said, that probably, Jesus was a middle-high class in economic sense, during the period of life before public ministry. I need historical references.
In order to address this question I have a few initial notes:
First, in first century Palestine, there wasn't really a "middle-class" in the same way that we think of it. The vast majority of people worked each day for their immediate necessities.
Second, we should look at Jesus before his traveling ministry and during his traveling ministry because we can presume that what he did for income was different: before he started his wandering ministry he was most likely a carpenter (Mark 6:3). When he started his ministry he became an itinerant Rabbi who relied on his audience for income.
Third, we have to first ask what does it mean to be a "poor man".
Before he started his wandering ministry, Jesus was a carpenter, meaning that he was of the small artisan class. Artisans were one of the only small social classes that had more economic means than the common class (the plebs) but were not in the highest social strata. So we can say Jesus came from a family with some, but small economic means. When he became a itinerant Rabbi, he relied on the charity of others (as was common for itinerant Rabbis) but he had the social clout of being a Rabbi.
In sum, the answer is complicated.
(Most of this info came from my college course on Wealth and Poverty in Christian History and from The Good of Affluence by John Schneider Chapter 5, near pages 123).
While this topic is heavily debated, Scripture records an interesting detail in Luke 2. When presented at the table, Joseph and Mary bring the appointed sacrifice:
22 When the time came for the purification rites required by the Law of Moses, Joseph and Mary took him to Jerusalem to present him to the Lord 23 (as it is written in the Law of the Lord, “Every firstborn male is to be consecrated to the Lord”[b]), 24 and to offer a sacrifice in keeping with what is said in the Law of the Lord: “a pair of doves or two young pigeons.
In Leviticus 14:21, we understand this was the sacrifice of the poor:
and two doves or two young pigeons, which he can afford, one for a sin offering and the other for a burnt offering.
This, along with the fact that Nazareth was teeny, tiny village outside of Sepphoris together draws a picture of a poor family.
Now, others have taken the gifts of the wise men in Matthew to suggest that Joseph and Mary eventually came into some money. (Who knows, maybe Joseph pulled a Gary Coleman on Jesus and sold the stuff for himself!)
In any event, by the time of Jesus' ministry, it is pretty apparent that he is poor. Otherwise, it would be very difficult to square a "better off" Jesus with Matthew 8:20:
Jesus replied, "Foxes have holes and birds of the air have nests, but the Son of Man has no place to lay his head."
And, considering Jesus' "preference for the poor" in Luke, it all comes together to suggest a less than rich Jesus.
Regardless, these Scriptural clues have made the traditional argument to be that Jesus was poor, although some modern theologians have constructed cases for a richer Jesus.
In addition to the answers already provided, I would like to draw your attention to a passage from Luke 8:1-3:
After this, Jesus traveled about from one town and village to another, proclaiming the good news of the kingdom of God. The Twelve were with him, and also some women who had been cured of evil spirits and diseases: Mary (called Magdalene) from whom seven demons had come out; Joanna the wife of Cuza, the manager of Herod’s household; Susanna; and many others. These women were helping to support them out of their own means.
That Jesus and His disciples had to rely on the donations of women (many of whom did not have their own source of income and so could not have given much), implies that they were far from wealthy.
Jesus did have some money, though He held it in common with the 12 disciples. But the Bible gives a strong hint that it wasn't much: when He sent the 12 out, He told them not to take a collection bag or even any money!
Dr. Adam Bradford wrote a book called 'The Jesus Discovery', in which he argues that Jesus was probably a (former) member of the religious elite who turned against them. This is evidenced by their behavior toward him, and and surprising respect they showed him (at least in public). He also makes the argument that the tradition that Joesph was a carpenter comes from a mistranslated Greek word, and that he was probably more akin to a modern day architect than a wood worker, and therefore would have had the means to send his son on to a high level of education.
Here is a debate on a UK radio program, between the author and new testament scholar, David Instone-Brewer, about this theory.
Paul describes himself as an imitator of Christ and as an 'architekton' (1 Cor 3:10) - a master tekton. Slater's lexicon translates tekton as architect. Priests trained as tektons to build the temple of Herod (Josephus' Antiquities). It would have taken devout Jewish tektons to train priests. I.e. like Joseph (Matt 1:19).
Jesus went to the Temple when lost (Luke 2). Presumably because he was known there + so would get looked after until Mary + Joseph caught up with him. He is admitted there as a 12 year old into the company of the Doctors of Law (Luke 2), presumably because they knew Joseph.
The offering for the poor was not means-tested. Any Jew, however rich, could make it, e.g. if they were at odds with the Sadduccee's corruption.
In any event Joseph received the Magis gifts after that. These were rich Babylonians making kingly gifts because they considered Jesus to be a king. There were enough of them to 'disturb Herod and all of Jerusalem' (Matt 2:3). They opened treasure-chests (plural) of the 3 most expensive items of the day. Much more wealth than needed for 2 years in Egypt.
Jesus had a house in Capernaum (Mark 2:1). He had 'nowhere to lay his head' because he spent so much time travelling and ministering.
Judas could steal from their money-box without it being immediately obvious (John 12:6).
I recommend Bradford's The Jesus Discovery.