Hello Cleo
It’s interesting to see that it is possibly a French Westwood tractor.
It’s great that you want to be hands-on and restore the tractor either for yourself or a new owner to use, and perhaps make a little money in the process and there’s nothing wrong with having a little money left at the end of the day.
As I’ve restored, exhibited and in order to buy something else or make space I’ve also sold several tractors too, I think I can give you a few pointers.
Generally after overhauling a machine I’ve found there’s never been a great deal of money left, if any. For me the pleasure has always been in preserving that particular machine so it can carry on working or being exhibited.
Not wanting to frighten anyone but to get a tractor into great condition costs can include: new tyres, new seat, getting the engine to run with new gaskets, oil, air filter, battery, carburetor kit etc, electrics inc key start and switches, drive belts and clutch, paintwork and decals. These do stack up! If the engine, gearbox, drivetrain are in running condition or any from the above list are working or in cosmetically good condition and can be kept then the better! Keeping as much of the original as possible is the way to go.
I’d recommend making a list of the items required and an estimate of cost. Then find out an approximate resale value from internet auction sites and deduct one cost from the other. It may be that it’s financially better (and less time consuming) to preserve the tractor as it is with a little cosmetic tidying rather than a full overhaul, but that can be a really difficult decision and is down to personal preference.
As for future values, unfortunately there are none, it’s pot luck what tractors make. Prices can fluctuate quite a bit depending on desirability, condition, location, time of year and if the tractor has any attachments such as a mower deck or snowplow.
Good luck with the tractor and hope it goes well.