Buddhist monks give advice for lay life Would you say that it is appropriate for a monk to give advice to the laity in how to live life/dealing with obstacles?

Now don't get me wrong, but monks certainly have "safer" environments. They are much less exposed to stimulating sensory input as well as life problems. I am by nature quite skeptical and cannot really take a monk serious if he gives tips and at the same time  does not follow these tips (or rather that lifestyle). How can a monk give relationship advice? Sure, the Dhamma gives such, but then it's just intellectual knowledge given by a monk, but that advice has not been practised by him.

I think the whole "problem" starts with titles like "venerable" or the admiration of monks/nuns. Again, don't get me wrong, seeing in them a role model and paying homage to them because they delivered proper dhamma is appropriate, but one should always keep in mind that they are UNIQUE, COMPLEX (in that they think, feel and do good, bad and neutral things) and FALLIBLE. 

Anyone made same experiences? Advice? Opinions?
In the same vein as ChrisW's answer, I would ask you, "You and I live different lives.  I do not live your life.  Is it appropriate for me to give advice?"  The answer is generally "yes," especially in the position you have chosen to put yourself in, asking us for advice on this forum. =)  So what is the difference between me giving you advice on a life I don't live and a monk giving you advice on a life he or she does not live?  One may argue that it's a level of differentiation, but that immediately begs the question of what level of differentiation is appropriate?

Indeed, is it not reasonable to seek advice from everybody?  I know that, in my culture, we prize the ability of children to see things through their young eyes and reveal what we cannot see ourselves.  Of course, we aren't obliged to follow their advice either.  If we were, my toddler would have far more cookies in her diet!

You point to the title of "venerable" as an object of concern.  Alan Watts had a line of reasoning in one of his lectures that addressed this issue.  He focused on the concept of the teacher, and asked "From what does the authority of a teacher come from?"  What gives a teacher the right to tell you what to do.  The answer he offered: "The authority of the teacher comes from the student."  If someone wishes to learn from another, they might say "hey, tell ya what.  I'll call you teacher, and you call me student," and from that the authority stems forth.

As you say, they are fallible.  But they have also devoted a tremendous amount of time to seeing the world through eyes very different from your own.  If they are willing to share their advice with you, that should be seen as a blessing.

I can call myself "venerable" if I want.  It's just a word.  Whether anyone wishes to act upon my claim is entirely up to them.  However, as a general statement, we find that the lay society has decided that when a monk or nun is called "venerable," we really mean it.  There is something special there.  You obviously don't have to take my word for it.  I have no authority.  But the fact that lay society accepts that monks and nuns can and should be given this title is something worth noting, and you should decide what to derive from it.  If I were in a position of authority, I'd argue that it indicates that your peers have found their advice is worth heeding, but as I stated, no authority here besides that which you give me.