LPG heating.. Any advice please...

[rainbowfeet]

Recently moved into an old cottage with LPG heating.. The LPG only runs heating & hot water.. Cooker/oven is electric..
How often should my 47kg bottles be lasting ? At the moment they are lasting me about 2 to 2.5 weeks each.. We only shower no baths.
Are there any mystery tips to working out when they are to run out.. Too heavy to lift. & swish around so using the hot water down the side method but not very scientific?!! ... Been a city dweller all my life so this is all new to me.. Thank you

Anyone

Good question Dh and I were looking at a lovely house and it has LPG central heat/hot water and I was wondering if it is very expensive to run compared to natural gas.
Hope someone comes by with experience soon

I'm finding it very expensive bottles are £58 each & getting through them in about 2 to 2 half weeks
Thank Goodness it's so mild at the moment I'm able to turn some rads off & limit use of heating, dreading it getting really cold.

We have LPG but in a big tank- might that be an option? Our company (flogas) will come and top it up every so often- they say so, but only new to this so I'm not certain how often it'll be!
As for price- MUCH more expensive than mains gas is what I've been told. But we don't have a lot of options.