Macro lens advise

Quite so. We are very spoilt these days. I once had a Voigtlander Dynarex 135mm lens for Bessamatic. Very nicely made, but close focusing was 13.5 feet! One reason the German camera industry started to lose out to the Japanese.

John, that's quite some distance
The 18-55 is the best close focusing zoom with 1:2,9 magnification, for normal sizes flowers that's good enough for tulips and things like that smaller flowers might be a problem.
The DA 17-70 is the second best pentax zoom lens with 1.3,1 magnification.

the Sigma 17-70 Macro sounds like it would focus very close but with 1:2,7 it's a bit disappointing

It's mostly down to mechanical design (the Bessamatic was a complex bit of engineering) and the laws of optics. As lenses focus closer, the light fall off changes the effective aperture. The aperture value holds well down to about 1:10, which is why 50mm lenses focus down to around 50cm (actaully 45cm for Pentax) - the design gets more awkward if you want to focus closer, and the price goes up.

Modern zooms seem to happily break all these optical rules - they don't really of course but new technology has found new solutions.

There seem to be a lot of Pentax 100mm DFA Macro for sale on eBay for £299 at the mo. At this price, I'm just surprised they are still for sale! Clicky

I did my bit and bought one, not from that seller though. It arrived and was exactly as described. Box a bit scuffed but otherwise unopened and brand new.

I haven't tried it yet, lens and I about 1000 miles apart, but if it lives up to expectations there could well be an SMCP-FA 100mm Macro available soon.

There seem to be a number of sellers all selling just this one pentax lens...all based in Manchester, so probably the same vendor!

Why that particular lens was chosen to grey-import in bulk then flog on ebay I've no idea...

'cos it's replaced with the WR version....

I have both the 50 and 100 macro lenses, and even though my macro centres on plants rather than insects I still greatly prefer the latter due to working distance. The 50 is great for indoor closeups, but if I could only have one for traditional outdoor macro I would have that. There are numerous alternatives to the DFA 100:
*The Tamron 90mm (~£350 new) and Sigma 105mm (~£380 new) are both extremely good lenses, comparable in image quality to the Pentax (it really is a tossup, I have the DFA100 because Park had them on offer at £270 a while ago!)
*Various old Pentax (e.g. 100mm f4) and third party (Vivitar-Tokina 90mm, Tamron 90mm) lenses. Bear in mind that some of the good ones can be upwards of £100 used - though obviously that is still about a third of the price of the new AF lenses

If I didn't already have both the D-FA and FA 100mm Macro lenses, at £299 I wouldn't hesitate for a second.

That is silly money for a fantastic lens.

Would something like this initially do the trick??
PENTAX SMC- F f/4-5.6 35-80mm A/F lens :
alternatively there is this one:
PENTAX A 28-80mm MACRO

There are some of them on Ebay.

Pentax F 35-70 is a good one. The 35-80 less so. None of these zoom lenses are true macros though, but they'll be fine for basic flower portraits of roses etc. A true macro will open up far more possibilities.

Reversing rings can do the trick as well, though you have to hold the aperture open on automatic lenses.. Check out Poor-Man's Macro on Flickr for some examples and other ideas.

Tamron 90mm is a great contender... and rated very well in reviews...
Check it at photozone.de...

Depends how cheap you want to go.

I use a Marumi close up filter to good effect on a digital compact with 72mm filter (not that compact...). It cost around £20 from Microglobe, and was well worth the money. Cameraworld also sell them and I am sure they would pair well with the kit zooms.

You could also use extension tubes, which will give great image quality but will certainly require a tripod. PKA extension tubes for Pentax are hard to find and expensive when you do (upwards from £50).

I would not hesitate to buy a manual focus macro lens - auto focus is not always terribly useful with a macro. I have a Pentax 50mm SMCM 1:2 lens which is pocketable and great quality. For longer reach, my first secondhand choice would be the original Tamron 90mm f2.5 lens. Around £100 if you can track a good one down.