Bob Rice VE3HKY, has a wonderful hi-def video on how to build a 7-Band Portable Dipole Antenna for $35.
Yes you read that right: $35.
If you’re new to Ham Radio you might not realize that all antennas with very few exceptions are merely dipoles. A dipole is an antenna that has two poles :)
Beams are dipoles with add reflectors and directors. A vertical antenna is a dipole with one pole buried in the ground. A VHF whip on your car uses the car body as one pole. A G5RV is essentially a dipole.
There are lots of commercial antennas that cost hundreds of dollars which are fancy variations on the dipole theme.
The unwary or uninformed can end up shelling out hundreds of dollars for something that looks good but doesn’t work as well as two pieces of wire fed in the centre with either coax (which will limit the antenna’s ability to tune on different bands) or open-wire feed which (when used with a tuner) will allow the antenna to tune up on multiple bands.
One of the issues with erecting portable antennas especially when on vacation is there maybe no trees or other supports at your vacation location. That’s where a self-supporting multi-band antenna can be really useful.
Bob’s hour long video will walk you though the construction process.