A wrench that fits the hub nuts:   If your bike has quick release front and rear wheels, you don’t need this, but if you have an internal hub on the back, such as the NuVinci, a wrench that fits is a great idea.  99% of the time, this is a 15mm wrench, but you should check your bike.   A 6 inch adjustable wrench can also work, but it will be heavier, and when using an adjustable wrench, you do need to take more care to not round over the nuts.   A fixed wrench is the best choice.    Some multi-tools have a 15 mm wrench built in, but again, if you have limited hand strength, something with more leverage is a great idea.
A bicycle costs anywhere from $250-$9,000 depending what type and quality of bike you want. A utility bike from a department store might cost $300-$500, but experts caution that it will be quite a bit heavier and not as well constructed as other bikes. For a durable, lightweight bike with front-suspension and decent parts, it’s reasonable to pay $750-$1,200. You might be able to pay slightly less, but expect to need some repairs after several months of heavy use.
Next, two-stage designs. There are two types of hand pump. HV (high-volume) pumps, ones that pump a lot of air but don’t have a lot of pressure, which are used for mountain bikes. The Lezyne Alloy Drive is a high-volume pump. Then there are HP (high-pressure) pumps, which pump a small amount of air but can inflate to very high pressures and are used on road bikes. Our top pick is a high-pressure pump.
Modern bottom brackets use a sealed bearing type construction that keeps water and debris locked out, so they seldom go wrong. Maintenance is impossible so they need replacing when they do wear out. Older style cup bottom brackets need to be re-greased every now and again, and occasionally will need to have their bearings replaced. There are a lot more teeth on the chainring cogs than those on the rear cassette, so need changing less regularly. Cranks usually a solid one piece construction so there is not much to go wrong.