There are several versions of the Sigma 400/5.6.

See e.g.
http://tesselator.gpmod.com/Images/_Equipment_n_Tutorials/SIGMA_400MM_5.6_APO.jp...

http://www.dyxum.com/images/Lenses/407/407_1.jpg

http://farm5.staticflickr.com/4148/5082965035_1f3e825e04_b.jpg

100 GBP is a good offer, if it is really already an APO version.
I think you could always sell it without loss, if you are not satisfied.

If you are looking for a 400/5.6 APO MACRO (in well used condition) than this might be interesting for you (499€):
http://forum.digitalfotonetz.de/viewtopic.php?t=98683
The seller is a well known member of the German forum dfn and also a moderator there.

359€

I do not know anything about the α-mount version of this lens.
Sony, however, does not offer SLRs any more.
It seems they now even say goodbye to the SLT technology.
If they will go fully mirrorless, prices for any α-mount lenses probably may drop significantly.

If one looks exclusively for long glass, Canon and Nikon might be a better choice.
Used manual glass is well below e.g. the A* 300/2.8.
An AF 300/2.8 ED is much less expensive than the FA* 300/2.8.
You might even get an additional professional body for the price difference.
However, in comparison to Canikon, you get image stabilization with the Pentax versions.

The Tamron 300/2.8 AF is a very rare lens in K mount.
It exhibits a metal body, which is on par with the A*.
Additionally, it features autofocus.
So, a comparable price imho is justified.

Currently, the Sigma 300/2.8 is the only alternative, which you can buy new for Pentax.
In Germany the MSRP is 3799 €.
Comparing prices online gives a best offer of 3049 €:
http://geizhals.de/sigma-objektiv-af-300mm-2-8-ex-dg-apo-if-fuer-pentax-195945-a...
Lens prices seem to be a bit lower in the UK, so there might be a slightly better offer there.







PS:
If you want to impress the ladies, you can use pink adhesive foil :
http://www.flickr.com/photos/stanlau/7024321375/in/photostream/

EU bank transfer probably would have been cheaper, but also slower and less secure for the buyer [+].
Once, money has been passed like this, there is no way for the buyer to get (some of) it back.

PayPal, might be more costly - for both the buyer and the seller.
I agree that some of the charges are a bit excessive [++].

But, in your case, one should rather look at the difference between getting a brick for £380 or getting it with (some) insurance for £393.
Also, be aware of the shipping costs [+++].

[+]
Note, that there might be several options.
But currency conversion from GBP to Euro always might be less favourable than expected.
I once transferred an amount of money in Euro this way and the British bank then used a much worse conversion rate (Euro to GBP) than my German bank would have done.
Additional transaction fees (UK to Germany) also can easily be in the 20 GBP range.

[++]
Currency conversion fee [about 3.5%]:
https://www.paypal.com/uk/webapps/mpp/cross-border-and-conversion-fees#currencyconversion
Fees for receiving payments from buyers outside your country [about 3.4%]:
https://www.paypal.com/uk/webapps/mpp/paypal-fees
Transaction fee for cross border payments [about 0.5%]:
https://www.paypal.com/uk/webapps/mpp/cross-border-and-conversion-fees#crossborder

[+++]
There is no possibility to send a parcel with insurance from Germany to the UK with DHL (DHL express is possible for XXX€).
Some rumors suggest that too many insured packages were lost in the UK by e.g. Parcelforce and Royal Mail.
This could be the reason for this status.
After several telephone calls, I strongly suggest UPS or FedEx for sending packets with valuable articles from/to the UK.

I know someone close to his destination.
So, I offered a personal handover with cash on collection.
However, my contact answered not within 1-2 days.
As alternative, I agreed on bank transfer - if a copy of the seller's ID card would be provided beforehand.
Additionally, I also offered payment via PayPal with all costs and fees covered by me.
After that he informed me that he has "agreed a sale to another member".
Maybe, I am a bit too suspicious - but sometimes, things are just too good to be true.

Deal finalised if personal handover works out.

Hi,

PayPal seems to be no option, maybe a trusted member here would do me a favour and manage a personal handover (I would cover all costs and add a reward for your help)? If not, you easily can register for PayPal (I again would cover all fees).

Regards,
froeschle

Hi,

I would take everything, if delivery to Germany and payment via PayPal is an option for you.

Regards,
froeschle

PayPal or EU bank transfer both are possible.
Insured shipping (roughly 100€) via UPS is preferred.