Horizontal propane tanks

Hello,
By chance and good luck I was able to pick up a used Propex heater for around $100. I had thought they were out of reach, so was very excited when I won the auction.
My trailer doesn’t have room for any propane tanks on the tongue, so I have been looking into horizontal tanks that can be mounted underneath.
For example:

Here are some options that will fit (all Manchester Tank models):
3.3 gal $470 @ VanCafe
https://www.vancafe.com/253070601D-p/253070601d.htm
5.9 gal $580 @ GoWesty
https://www.gowesty.com/product/lp-tank/4323/lpg-tank-
6.7 gal $599 @ Campervan HQ
https://www.campervan-hq.com/products/rv-propane-tank-6-7-gallon-manchester-model-6811
The first is 6” diameter and the other two are 8” diameter. Prices are better for 10” and 12” diameter tanks but I don’t want to lose the ground clearance. Also, the capacities are actually 80% of what is listed because there has to be room for gaseous propane above the liquid.
All of these seem crazy expensive compared to your normal vertically mounted tank, which can be had for under $100.
Does anyone run an underslung horizontal LPG tank like this? If so, where did you find it? Do you like it and is it convenient to fill up and to use? Do you wish you went with a portable conventional tank instead? Thanks in advance for any insights as I plan my Propex heater setup.
Lauren

By chance and good luck I was able to pick up a used Propex heater for around $100. I had thought they were out of reach, so was very excited when I won the auction.
My trailer doesn’t have room for any propane tanks on the tongue, so I have been looking into horizontal tanks that can be mounted underneath.
For example:

Here are some options that will fit (all Manchester Tank models):
3.3 gal $470 @ VanCafe
https://www.vancafe.com/253070601D-p/253070601d.htm
5.9 gal $580 @ GoWesty
https://www.gowesty.com/product/lp-tank/4323/lpg-tank-
6.7 gal $599 @ Campervan HQ
https://www.campervan-hq.com/products/rv-propane-tank-6-7-gallon-manchester-model-6811
The first is 6” diameter and the other two are 8” diameter. Prices are better for 10” and 12” diameter tanks but I don’t want to lose the ground clearance. Also, the capacities are actually 80% of what is listed because there has to be room for gaseous propane above the liquid.
All of these seem crazy expensive compared to your normal vertically mounted tank, which can be had for under $100.
Does anyone run an underslung horizontal LPG tank like this? If so, where did you find it? Do you like it and is it convenient to fill up and to use? Do you wish you went with a portable conventional tank instead? Thanks in advance for any insights as I plan my Propex heater setup.
Lauren
