Don't know about post office in Mombasa if they are reliable, but the ones in Nairobi are; gonna say nowadays most packages arrive to destination, a lot of progress from Posta the last few years
Anybody from Mombasa ??
In general, it depends a lot of Custom agent on service on D-day and how your friend is behaving; if he is behaving like a newbie than he may be fooled or charged heavy price.
For your information, all package are opened at post office in front of Custom agent who then fix a value of items. Then, fees are 25% of value, do the total and add 16% of vat. In Nairobi, they check on Google Checkout or ebay to get value, so your friend is not happy but given value, he can ask to check online or go out go to cyber cafe and find better price (happened to me once, was browsing while the guy was browsing in his office, he gave a value and said no, look here, and he checked again and gave correct value)
ex - if value item is 1000 KSH, custom fee are 250 Ksh
Then VAT is 16% of 1250 ksh (value + fee)
Some more tips:
Scolar and educational books are VAT free (or both, don't remember). Same for cameras and all camera expenditures (film, flash, tripod)
If you sending new items, remove all packaging and make it look like used item. I know people who scratch the item, put stickers, etc...
Don't send something which is cheaper here than in your country like phones or electronics
Shipping method ?
The clean method - As they above, if you insured it and declare full value of item (usually on document with clean invoice inside) - 100% guarantee + item is fully insured, and you know how much your friend will be charged.
Other methods
Send it insured but lower value item (if second-hand items, used items, etc.) - if lost, you are only reimbursed declare value
Send it uninsured - then up to you if you declare full value item or lower it; you can mark it as gift, but the same, package will open and blah, blah... So always put a value to items sent to facilitate the process; you can put copy of invoice or even write a small paper with items and your value if you are sending many. It's up to you !!
Lasst, if you want to reimbursed your friend or even send a gift onlie, they is a Kenyan website which enable you to send voucher or phone credit or electronic gifts. You just pay through the website via Paypal, Visa or Western Union, and your friend get a voucher or money, (see mamamikes.com)
TheBigBoss