This looks very much like a scam. Apart from a very strange payment procedure,
which is a huge red flag in itself, I see at least three more red flags.
Firstly, the price is quite low, as you mention.
Secondly, he says that he will have to pay 79 euro to "Booking". This is a common trick employed by scammers — make you think that the scammer spends their money on you, so that you feel obliged to do what they ask. I guess this trick should have a name and a Wikipedia page...
Finally, his excuse for all this trouble sounds very weak and illogical to me. He says he is doing this to make sure you have the needed money, so that he will not go to Eindhoven for nothing. However, I suppose that not having money is by far not the most common reason to get out of a potential rent agreement. Way more common are just "I did not like the property" or "I liked a different property better". So even if you do have money and can prove it to the landlord by this escrow-like transfer, this in no way guarantees that he will not travel to Eindhoven for nothing. Moreover, he clearly says that you will be able to cancel everything, so he clearly understands that he may get nothing from his trip... The logic does not add up.
So what is the most probable outcome? Most probably, they will send you a phishing link that will make you think you are paying on real booking.com, while it is not so. The most common ways are:
- some legitimate-looking domain, but not affiliated with booking.com, e.g.
booking-long-time.com
or long-time.booking
- a domain visually similar to booking.com, but with a small typo, e.g.
bookimg.com
or bookıng.com
, or something like booking.com.someothersite.com
- maybe they have found a way to send you an authentic booking.com link that will redirect you to the scammer's site (e.g. something like
booking.com/redirect?to=http://foobar.com
), or that allows them to inject their content into a legitimate booking.com page; such vulnerabilities are not unheard of.
Note that there are other, more subtle ways to trick you into paying money to them. Should you decide to follow up, after learning more details from them, you can ask an updated question (probably better suited for Money Stackexchange) to find out how a particular scam can work.
I would suggest you don't follow up and completely block their account.
However, if you are as curious as me, you can try to agree to them just to see what will happen next. You will at least learn something yourself, and (not very probable) maybe you will even find something that the authentic booking.com support will be glad to hear about (e.g. some vulnerability on booking.com site).
I have done this once (with a similar, but different scheme, on a classified advertisements website), only to see that indeed the scammer sent me a typical fishing site with a small typo in the domain name. I dropped all messaging with the scammer and reported it to the website's support (although I don't think this is a viable way to combat that particular kind of scammer; this was not an actual vulnerability, just plain old phishing).
Just be sure not to pay anything and not to enter any your data (credit card details, ID details, etc.) anywhere, and do not trust anything they say. In particular, if you raise your suspicions with them ("the link looks strange..." etc.), they may try to offer you millions of explanations ("this is a special booking.com domain for long-time rent", etc.) Do not believe this.