Worth replacing the hard drive, battery and buying recovery disks?

I currently have a Lenovo laptop and have had it for 2 and a half years. The battery has always been pretty bad and last about 3 minutes unplugged. The hard drive is a temperamental one from an old laptop as the original broke for no apparent reason, probably didn't help I was constantly having to rebuild it too. I know it is stupid but when I got this laptop I was young and naive and didn't realise how essential recovery disks are.
I realise to replace all of these would be quite expensive so am wondering whether it is worth just buying a new laptop?

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There are at least 7 levels of Lenovo laptop... Is this a T-series... or just what is it? model and type.
In general, Lenovo laptops are among the most reliable...
This is not a good time to buy hard drives, due to the market over-adjusting to the hard drive factories under water in Thailand.
Batteries, good ones, can be found for $35 to $45
But you can get a 90 GB SATA hard drive for $90 or less.
Tell us the hard drive brand and size, the amount of memory installed.
All in all, we can rebuild a decent Lenovo for $140... and that is a lot less expensive than a new laptop. But a shop would have to charge you $205 or more.
A cheap laptop might cost you $500 to $600, but a good laptop could cost you $1200 to $1800. For long term reliability, I would want to invest at least $1000 to $1500

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