Tried research what could find on Garmin site but w/ my slow dialup was
too painful to delve deeply.

Best I could see appears that WAAS of roughly 10-ft (3-m) is best could
hope for. This is, I presume, all any moderate/low-cost device has?

Need/desire is to layout acreages for ag purposes--haying, etc. Need
accuracy to roughly 0.1A out of typical 80 to 160A patches. Note that
1A is 16.5-ft (1 rod) by 1/2-mile for thinking purposes. Hence, if
10-ft is best I can find a corner at one end, that's 2/3-rds an acre
roughly so really need about 1-ft. One advantage is it's flat, no
trees, no other obstructions.

Anybody have any detailed knowledge of abilities of units and how well
suited would be to start in a corner of a field and mark a line at other
end 1/2-mile away parallel to hit (say) 80A out of a quarter-section
(160A). I can locate most boundaries reasonably well by existing roads,
old fence rows that are visible if know what looking for, etc., altho
there are a couple of places that have now been in grass for nearly 30
years that don't have any visible landmarks any longer between quarters
that were all farmed together and now can't find specific location of
half-mile lines as no corner posts or other landmarks remain. Field
technician from FSA (Farm Service Agency) came out w/ their high-priced
system last year and marked one of these corners for me; he brought his
Jeep Wagoneer. We got out to place the stake and probably less than
20-ft from it turned around and couldn't find it in the grass... Not
much of it is that tall, but that quarter was last year; we made over
400 large round bales off a little under 80A.

Anyway, any input appreciated...

The ag manufacturer's tractor-mount systems are 6" or so, but they're
also multi-k $$ and this function doesn't need the ancillary crop
software, etc., just waypoints...

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